When they want to find the best in contemporary fiction writing, people often think of The New Yorker, Granta, or any number of small circulation literary magazines. When the subject is foreign policy, however, I'll take the Wall Street Journal op-ed page. Apart from maybe running a spell-check program on submissions, it's hard to see any sign that the editors there care about factual accuracy, provided that the piece in question satisfies their hawkish proclivities and other litmus tests.

So here's a little game you can play with one of their recent entries: Andrew Roberts' May 1 piece that invokes various historical examples to justify a preemptive strike by Israel on Iran. Your challenge: How many bald-faced errors can you spot in a single short piece?

First, let's start with the title: "The Case for Preemptive War." In fact, what Roberts is advocating in this piece is not pre-emptive but preventive war, and there is a big difference. A preemptive war is a military campaign launched in anticipation of an imminent enemy attack: You strike first because you know the opponent is getting ready to attack and you want to seize the advantage of striking first. Preventive war, by contrast, is a war launched to take advantage of favorable conditions (such as a favorable balance of power), even though the intended target is not in fact preparing an attack of its own. Preemptive war is sometimes permissible in international law; preventive war is not.

There is of course no serious evidence that Iran is about to attack Israel, and experts even disagree over whether Iran is actively trying to develop nuclear weapons. The U.S. intelligence community still believes there is no active nuclear weapons program underway. So Roberts' entire piece is based on a category mistake, which is not an auspicious way to begin.

Second, Roberts refers to Israel's "successful pre-emptive attacks on Iraq's Osirak reactor in 1981." These attacks were a tactical success (i.e., the reactor was destroyed) but a strategic failure, as they convinced Saddam Hussein to get serious about developing WMD and to accelerate a covert nuclear weapons program whose full extent we didn't discover until after the 1991 Gulf War. The real lesson for today is that an Israeli preventive attack on Iran might be just the thing to convince the clerical regime that it really does need a genuine nuclear deterrent. That's the policy that Israel adopted back in the late 1950s, when it began its own nuclear program, and that's the lesson Saddam drew in 1981. Why wouldn't the mullahs see it the same way?

Third, Roberts declares that Israel's "preemptive strike" on Egypt in 1967 "saved the Jewish state." This is nonsense. Although Nasser's decision to order the U.N. peacekeepers out of the Sinai and to send part of his army back in was both provocative and foolish, he was not preparing to attack Israel and Egypt's forces in the Sinai were not deployed for offensive action. Strictly speaking, the Six Day War wasn't preemption, though some Israeli leaders may have seen it that way. Israel had more troops arrayed against the Egyptian forces, and U.S. military intelligence correctly predicted that Israel would win easily even if the Egyptians attacked first. No less an Israeli patriot than Menachem Begin described it accurately when he said: "The Egyptian Army concentrations in the Sinai approaches do not prove that Nasser was really about to attack us. We must be honest with ourselves. We decided to attack him." That attack might have been justified on other grounds -- such as not allowing Nasser to alter the status quo in the Sinai -- but it was not a case of preemption and thus does not support Roberts' case.

(By the way, readers interested in understanding the origins of 1967 war would do well to avoid Israeli Ambassador Michael Oren's highly imaginative reconstruction, and rely on more serious scholarly accounts, such as Tom Segev's 1967 or Roland Popp's 2006 article "Stumbling Decidedly into the Six Day War.")

Fourth, most of Roberts' other examples are misleading or inapt, because they are not the "bolt-from-the-blue" acts of preventive war that he is advocating. Instead, the actions he describes -- such as the "Copenhagening" of the Danish fleet by the British in 1807 or the scuttling of the French fleet in Oran in 1940 -- were simply acts of strategic initiative undertaken in the midst of active and open hostilities. As such, they tell us nothing about the wisdom of launching an unprovoked preventive war with Iran today.

Finally, Roberts' entire case rests on the dubious belief that Israel has the military capability to inflict a decisive blow against Iran's nuclear infrastructure. There's little doubt that Israel could damage Iran's enrichment and reprocessing capability. But it cannot destroy the underground facility at Fordow, and it can at best delay Iran's nuclear potential by a few months or years. The fact of the matter is that Iran already knows how to get a nuclear bomb if it ever decides it really wants one, and repeatedly threatening it with regime change and possibly conducting a preventive (not preemptive) strike would be the single best way to convince them to go all-out for a full-fledged nuclear capacity. The only way to prevent an Iranian bomb is to convince the regime that it doesn't need one, but the strategy Roberts recommends would have the opposite effect.

The Wall Street Journal is a distinguished newspaper with an enormous and influential readership, and its reportage is often impressive and fair. But its op-ed page has been off the deep end for as long as I can remember. It should not be forgotten that the Journal's editors and commentators were among the most fervent advocates of invading Iraq, a modest little adventure that didn't turn out so well. All of which suggests that the paper really ought to come with a warning label, or perhaps a color-coding scheme that tells readers when they've left the world of facts and logic and entered into the realm of fiction. Or if that is asking too much, how about a bit of fact-checking?

Today's example of sloppy journalism comes from the exalted pages of the New York Times. Here's the key passage, from an article reporting recent poll results showing that the American people are not enthusiastic about intervention in Syria:

"Americans are exhibiting an isolationist streak, with majorities across party lines decidedly opposed to American intervention in North Korea or Syria, according to the latest New York Times/CBS News poll."

Got that? If you're one of those people with doubts about the wisdom of intervening in Syria, you're an "isolationist." At a minimum, you're "exhibiting an isolationist streak."   

A degree of prudent skepticism about the wisdom of entering the Syrian morasse is not isolationism, of course. Genuine isolationism would mean severing our security ties with the rest of the world and focusing solely on defending sovereign U.S. territory. Genuine isolationism means ending U.S. alliance commitments in Europe and Asia and telling our various Middle Eastern allies that they were going to have to defend themselves instead of relying on help from Uncle Sam. Genuine isolationism would eliminate the vast military forces that we buy and prepare for overseas intervention and focus instead on defending American soil. Real isolationists favor radical cuts to the defense budget (on the order of 50 percent or more) and would rely on nuclear deterrence and continental defense to preserve U.S. independence. And the most extreme isolationists would favor reducing foreign trade and immigration, getting out of the U.N. and other institutions, and trying to cut the United States off from the rest of the world.

The overwhelming majority of people who have doubts about the wisdom of deeper involvement in Syria -- including yours truly -- are not "isolationist." They are merely sensible people who recognize that we may not have vital interests there, that deeper involvement may not lead to a better outcome and could make things worse, and who believe that the last thing the United States needs to do is to get dragged into yet another nasty sectarian fight in the Arab/Islamic world. But many of these same skeptics still favor American engagement in key strategic areas, support maintaining a strong defense capability, and see some U.S. allies as assets rather than liabilities.  

Hawks like to portray opponents of military intervention as "isolationist" because they know it is a discredited political label. Yet there is a coherent case for a more detached and selective approach to U.S. grand strategy, and one reason that our foreign policy establishment works so hard to discredit is their suspicion that a lot of Americans might find it convincing if they weren't constantly being reminded about looming foreign dangers in faraway places. The arguments in favor of a more restrained grand strategy are far from silly, and the approach makes a lot more sense to than neoconservatives' fantasies of global primacy or liberal hawks' fondness for endless quasi-humanitarian efforts to reform whole regions. 

Bottom line: The Times did its readers a disservice by using the pejorative term "isolationism" in such a sloppy fashion. As Brad DeLong likes to say: "Why, oh why, can't we have a better press corps?"   

One of the great successes of the Obama administration has been its ability to divert attention from the wars the United States is still fighting, such as Afghanistan. Given Obama's decision to escalate and extend that war is looking worse and worse with time, you can understand why they are doing this. It's possible that sending more troops bought Obama time and is making it easier to get out now; the problem is that we ended up squandering more lives and money without getting a significantly better outcome.

My real fear is that this is merely a preamble to telling ourselves a lot of self-serving myths about that war. Count on it: Our exit from Afghanistan will be accompanied by a lot of feel-good stories about the U.S./NATO effort there designed to convince Americans that the surge "worked" and that we really did give it our all. If things go south later on, that will be the Afghans' fault, not ours, and so it won't be necessary to learn any lessons from our mistakes. 

But two recent news stories suggest a very different read. The first, from Saturday's New York Times, offered an account of the farewell gathering for the deparating French Ambassador in Kabul, Bernard Bajolet. According to the Times, Bajolet told the attendees:

"That the Afghan project is on thin ice and that, collectively, the West was responsible for a chunk of what went wrong, though much of the rest the Afghans were responsible for. That the West had done a good job of fighting terrorism, but that most of that was done on Pakistani soil, not on the Afghan side of the border. And that without fundamental changes in how Afghanistan did business, the Afghan government, and by extension the West's investment in it, would come to little."

And then there was this passage:

"At his farewell party, Mr. Bajolet wound up his realpolitik with a brisk analysis of what Afghanistan's government needed to do: cut corruption, which discourages investment, deal with drugs and become fiscally self-reliant. It must increase its revenues instead of letting politicians divert them, he said."

Think about that statement as you read the second story (from today's Times) describing the millions of dollars of slush funds that the CIA has paid to Afghan President Hamid Karzai. But instead of purchasing Karzai's loyalty or enhancing U.S. influence, the money merely contributed to the endemic corruption that has marred the NATO effort from day one. As the Times reported:

"The biggest source of corruption in Afghanistan," one American official said, "was the United States."

There you have it: The French ambassador (and everyone else) says the Afghan government needs to reduce corruption, yet a key element of the U.S. effort there has been contributing to that problem. I wonder if H.R. McMaster, the general who was assigned to head up NATO's anti-corruption efforts in Afghanistan, knew what the CIA baksheesh office was up to. If so, he'll be in a great position to write a sequel to his earlier book on the U.S. failure in Vietnam.

Does the possibility (likelihood?) that Syrian government forces have used sarin gas strengthen the case for military intervention or at least great U.S. involvement?

Pro-intervention hawks like Sen. John McCain certainly think so and have been quick to remind everyone that President Obama called chemical weapons use a "red line." But McCain has been a vocal advocate of greater U.S. action for quite some time, which suggests that the use of chemical weapons hasn't really altered his thinking at all. Nonetheless, it is also worth noting that far more sensible commentators -- such as former CIA analyst Emile Nakhleh -- also view these reports as an additional reason to topple Assad sooner rather than later.

But why? Nobody should be pleased that Assad's forces (may) have used chemical weapons, but it is not obvious to me why the choice of weapon being used is a decisive piece of information that tips the balance in favor of the pro-intervention hawks. It's been obvious for decades that the entire Assad regime was nasty, and it's been equally clear that the government forces were using lots of destructive military force to suppress the opposition. How else did 70-80,000 Syrians die over the past two years? It's not as though Assad has been acting with great restraint and sensitivity to civilian casualties and then suddenly decided to unleash sarin gas. Does it really matter whether Assad is killing his opponents using 500-pound bombs, mortar shells, cluster munitions, machine guns, icepicks, or chemical weapons? Dead is dead no matter how it is done.  

The case against direct U.S. intervention never depended on believing that Assad was anything but a thug; rather, it rested first and foremost on the fear that intervention might make things worse rather than better. Specifically, it has rested on the interrelated concerns that 1) the fall of the Assad regime might unleash an anarchy of competing factions and warlords, 2) the opposition to Assad contained a number of extremist groups whose long-term agendas were worrisome, and 3) pouring more weapons into a society in the midst of a brutal civil war would create another Afghanistan, Iraq, or 1970s-era Lebanon. These prudential concerns still apply, irrespective of the weaponry Assad's forces have chosen to employ. And if his forces have used chemical weapons, then one might even argue that it raises the risks of intervention and thus strengthens the case against it.

This is not an open-and-shut issue, and there are obvious points to make on the other side. Obama did suggest that chemical weapons use might be a "red line," in what was a fairly transparent attempt to deter Assad from going down that road. So one might argue that Washington would incur some loss of credibility if it does not respond now. Although I think we routinely exaggerate concerns about our credibility, that doesn't mean that it is of no concern at all. Nonetheless, Obama's prior statements do not require any particular response, and the administration certainly shouldn't do something unwise simply because it feels it has to do something.  

One might also argue that chemical weapons are a form of WMD and that allowing Assad to get away with their use will undercut the existing taboo against these weapons. There's a case for that point of view, but I think it exaggerates the supposedly "unique" lethality of chemical weapons. Sarin is very bad stuff, but it is not like a nuclear weapon. Nor should we forget that governments can sometimes kill lots of people using rather simple weapons -- in the Rwandan genocide, they did it with machetes -- and the overwhelming number of deaths in Syria have occurred through conventional means.  

Like Senator McCain, I find my position on this issue unchanged by the revelations about possible chemical weapons use. I still see Syria as a tragically vexing policy question. It is heart-wrenching to see what is happening there and the instinct to "do something" is understandable, but the downsides to direct or indirect military involvement remain formidable. I certainly think we should be doing more to help refugees and to minimize the destabilizing effects of the carnage on Syria's neighbors. I am all in favor of continued diplomatic pressure on Russia and China to end their support for Assad, and the chemical weapons report may provide additional leverage on that point. (See here for some useful thoughts along those lines). But I hope that Obama doesn't allow himself to be bullied into doing a lot more simply because of these reports, unless he is convinced that doing more now reduce the risks later on.

One of the cool things about being as powerful and fortunate as the United States is that you get to preach to other countries about how they ought to behave. In that spirit, the U.S. State Department puts out a human rights report every year, and basically wags its finger at countries that don't measure up. Of course, the report tends to go easy on close allies, but it's still a useful document. Among other things, it provides data that scholars interested in human rights can use to test their ideas about the causes of violations and the policies that might alleviate them.

But as you might expect, the world isn't just sitting around and passively accepting report cards from Washington anymore. Case in point: China has just released its own human rights report on the United States, and it makes for rather interesting reading. It's hardly an objective assessment of life in America, of course, but much of the information contained within it is factually accurate. The incidence of gun violence and crime in the U.S. is far above the level of other industrial democracies, and having the world's highest incarceration rate is not exactly consistent with being the "Land of the Free." 

China's point is that the United States is being pretty hypocritical in singling out other countries, and maybe we ought to remove the log in our own eye before we start telling everyone else what to do. Add to this the recent bipartisan report confirming that Bush-era officials authorized the widespread use of torture and the fact that none of them has ever been indicted or prosecuted, and American hypocrisy on this score looks even more damning.

The Chinese report may not be objective, and the fact that U.S. leaders authorized torture does not mean Washington hasn't done plenty of morally admirable things too. But this gap between America's professed ideals and its actual behavior matters. Not just in moral terms, but in terms of power and global influence too. Smaller and weaker states are more likely to tolerate American primacy if they think the United States is a generally good society and led by individuals who are not just ruthlessly self-interested. They will be more willing to tolerate the asymmetry of power in America's favor if they think that power is used for the greater good. The more that others view the United States as hypocritical, self-absorbed, and indifferent to others, the more likely they are to ignore U.S. advice and to secretly welcome those moments when the U.S. gets taken down a peg or two.

The 9/11 attacks produced an unusual outpouring of sympathy for the United States ("nous sommes toutes Americains" headlined Le Monde), and we've seen a similar reaction in the wake of the Boston Marathon bombings. But such expressions of solidarity tend to be fleeting and especially when  U.S. behavior gives opponents an easy way to heighten dissatisfaction with America's global role. What's going on here is a struggle for legitimacy in the eyes of the wider world, and it would be foolish to believe that we will win that struggle just because we're the "good guys." That may be how we see ourselves, but Americans are only 5 percent of the world's population, and plenty of other people around the world have a rather different view.

The more I think about the events that transfixed Boston and the nation last week, the more troubled I am. Not by what it says about the dangers we face from violent extremists (aka "terrorism"), but for what it says about our collective inability to keep these dangers in perspective and to respond to them sensibly. I am beginning to wonder if our political and social system is even capable of a rational response to events of this kind.

Don't get me wrong: The speed with which the Tsarnaev brothers were identified was remarkable, and citizens at the scene of the bombing showed resolution and humanity in helping the victims. Here in Boston, a great many people worked with energy, courage, and effectiveness to identify and apprehend the perpetrators. And one can only feel a sense of heartache and tragedy when reading about each of the victims, senselessly murdered. 

It's the larger response to the tragedy that worries me. Although politicians from Barack Obama to Deval Patrick offered up the usual defiant statements about America's toughness and resilience in the face of terror, the overall reaction to the attacks was anything but. Public officials shut down the entire city of Boston and several surrounding suburbs for most of the day, at an estimated cost of roughly $300 million. What did this accomplish? It showed that a 19 year-old amateur could paralyze an entire American metropolis. As numerous commentators have already pointed out, a city-wide lockdown is not what public officials have done in countless other manhunts, such as the search for rogue cop Christopher Dorner in Los Angeles. And Dorner was a former Navy reservist who had killed four people and who was at least as "armed and dangerous" as the Tsarnaevs. Ladies and gentlemen, this is not the attitude that tamed the West, stopped the Third Reich, or won the Cold War.

The media frenzy that accompanied these events was equally disturbing. If terrorists "want a lot of people watching," then that's precisely what the American media gave them. It is probably unrealistic to hope that today's hydra-headed and commercially voracious media would respond to an event like this with even a modicum of restraint, but the feeding frenzy that CNN, Fox, and many other outlets engaged in must have been deeply gratifying to America's enemies. Television networks have learned not to train their cameras on the lunkheads who sometimes jump out of the bleachers and race across a baseball field. In a perfect world, these same organizations would act with similar wisdom when terrorists strike. In particular they would tell the public what it needed to know for the sake of safety, but they would spare us the round-the-clock, obsessive-compulsive, and error-ridden blather that merely gives extremists the publicity they seek.

As Boston shut down and the world watched, fourteen Americans were killed and more than 200 were injured in a factory explosion in Texas. Those people are just as dead as the four victims in Boston, yet their story is already fading to the back pages of the major papers. Meanwhile, the Tsarnaevs remain the Big Story and got profiled on 60 Minutes last night. As I write this, the death toll from last week's earthquake in China nears 200 -- with thousands injured -- but it barely rates a  passing glance. And the week before the Marathon bombing, those courageous members of our bought-and-paid-for Senate rejected the very mildest of efforts to reduce the danger from guns, even though firearms kill over 30,000 Americans every year. As Michael Cohen noted in the Guardian, we fear that which scares us, but not the things that actually threaten us.  

What is it about terrorism that terrorizes? Is the disproportionate attention it receives due to its seemingly random nature? The sense that it could strike any of us without warning? That explanation seems unlikely, given that other equally random dangers pose a greater risk. Is it because terrorism is the product of human volition, an explicit act of malevolence? This may have something to do with our tendency to overreact, yet other equally heinous acts don't seem to transfix society in the same way. 

Or was it the intrusion of an act of wanton violence into an event -- the Boston Marathon -- that is supposed to be celebratory and fun? Or do we react viscerally to terrorism because such acts force us to think -- however reluctantly -- about the rage, animosity, and alienation that others feel towards us?

I don't know. But I cannot help but think that our political leaders have been letting us down ever since 9/11. Instead of teaching Americans that that actual risk from terrorism was minimal, they have kept us disrobing in security lines, obsessing over every bizarre jihadi utterance, and constantly fretting about the Next Big One. An entire industry of "terrorism experts" has arisen to keep us on the edge of our seats, even though many other dangers pose a far greater risk. The result of this obsession has been catastrophic: a failed effort to nation-build in Afghanistan, a wholly misbegotten war in Iraq, and an enormous distraction from any number of other issues -- education, climate, energy, the economy -- whose mismanagement will ultimately claim far more lives and create far more immiseration than those two misguided and angry young brothers did.

I do not mean to trivialize what happened last week. Four innocent people died, and many more were grievously hurt. Finding the persons responsible was necessary, and I'm as happy as anyone else that they are no longer at large. But the brutal reality of human existence is that it is fragile, and there are no guarantees. Bad things do happen to good people, and it is the task of our political leaders to help us keep our heads even when awful things occur. The grossly disproportionate reaction to the Marathon attacks tells me that our political system is increasingly incapable of weighing dangers intelligently and allocating resources in a sensible manner. Unless we get better at evaluating dangers and responding to them appropriately, we are going to focus too much time and attention on a few bad things because they happen to be particularly vivid, and not enough on the problems on which many more lives ultimately depend.

I was up early this morning to get ready for a conference presentation at Harvard only to discover that Boston and the surrounding suburbs were in lockdown and that the university was closed for the day. Like most of you, I've been following Twitter and other news sources as law enforcement officials seek to corner the second suspect in the Boston Marathon bombings. Blogging during a rapidly developing story can be dicey, but here are a few quick thoughts.

As I tweeted a couple of hours ago, knowing the suspects' origins doesn't tell you what their motives were. Let's assume that the two Tsarnaev brothers really did it (which is certainly where the publically available evidence seems to point). The fact that they were of Chechen origin raises various possibilities, but at this point in time we have no idea if their actions were inspired by Chechen nationalism, by anger at America, by some weird personal animosity or desire for glory, by religion or by something entirely different. The man who conducted the Virginia Tech massacre, Seung Hui-Cho, was a South Korean national, but his actions stemmed from mental illness rather than his national or ethnic identity. Until we know more, inferences about motive based on the suspects' origins are little more than guesses.  

Whatever their motives were, it certainly doesn't appear to be some sort of well-oiled terrorist plot. As one tweeter I read noted, a sophisticated and well-financed terrorist organization doesn't try to stick up a 7-11 a couple of days after the attack. To see in this tragedy some rebirth of al Qaeda or "terrorists of global reach" seems misplaced, at least based on what we know now.

But as I suggested a couple of days ago, that observation doesn't change our situation very much. Given the nature of destructive technology -- in this case, fairly primitive bombs -- and the fact that there will always be a few people with a destructive agenda of some kind, there are always going to be senseless acts of violence. Governments and society at large can and should take reasonable measures to reduce that risk -- and yes, a saner approach to gun regulation would help -- but 100 percent safety isn't possible. Fortunately, the odds that any of us will ever experience a direct encounter with this sort of violence are still vanishingly small. Even if you're a police officer or a soldier, the odds are in your favor. For the rest of us, we are still remarkably safe by historic standards. And Americans are much, much safer than people in many other places.

And remember, four people have now died in Boston (not counting the dead suspect), but some fifteen people died in Texas when a fertilizer plant blew up. The world is not foolproof. Bad things do happen. That bedrock reality is not even interesting; what matters is that we recognize dangers for what they are, calibrate them properly, and respond to them intelligently.

P.S.: Continued kudos to the law enforcement agencies dealing with this problem, who identified the suspects with remarkable speed and have handled an extremely difficult situation with calm but decisive measures. Cable TV? Not so much.

Update:  As I've watched today's events and pondered further, I've become convinced that public officials in Boston erred by locking down the City and most surrounding suburbs for an entire day.  There may be a good explanation for this decision, but it hasn't been provided yet.  The economic cost has been enormous (by one estimate about $1 billion), and it sets a worrisome precedent if a 19 year old fugitive can paralyze an entire metropolitan region.  We didn't shut down DC when the snipers were operating there, and we didn't shut down Los Angeles when a renegade and heavily armed police officer was a fugitive.  This response also belies our insistence that we're tough and we won't be intimidated.  On the contrary: we look skittish and scared.   I suspect public officials were deathly afraid of further violence, and of being blamed later for not taking precautions.   We'll see.   But I worry that potential copycats will be inspired rather than deterred by the combination of media frenzy and governmental overreaction. 

I do not know what I would say to any of the victims of yesterday's attack at the Boston Marathon -- to the families of the three people who have died or to those whose lives have been irrevocably altered by the blast. For them, this is simply a tragic moment of ill-fortune, to have been in the wrong place when some evildoer planted a senseless bomb. 

For the rest of us, however, there are already lessons to be drawn. For me, the most important thing to remember is that such events, however vivid, shocking, and tragic, do not in fact pose a mortal threat to our society and our freedoms, unless we let them. For as horrible as yesterday's events were, Americans are not in fact at greater risk than they were before. There have been numerous bombings and other forms of mass violence on American soil in the past, and there will be in the future. Yet the odds that any American will in fact be affected by terrorist violence of any sort remains astronomically small. And so long as future incidents do not involve weapons of mass destruction -- and especially nuclear weapons -- then their impact will be limited to a few unlucky individuals who tragically happen to caught in terrorism's web through no fault of their own.

Thus far, the response to this outrage has been encouraging. For the most part, people have refrained from ill-informed speculation about responsibility. Boston and Massachusetts officials responded intelligently, swiftly, and calmly to yesterday's events, and ordinary citizens at the scene reacted in ways that makes one proud of our common humanity. If the perpetrators were seeking to sow confusion and panic or trigger some sort of massive over-reaction, they failed. I am confident we will eventually find out who did this and that they will eventually be brought to justice. 

There are now over 7 billion human beings on this planet, and roughly 313 million citizens here in America. It is inevitable that a tiny handful of these individuals will be driven by their own beliefs or demons to commit deliberate acts of violence against innocent people. And there is no reasonable way to prevent a few of those individuals from getting their hands on the materials needed to make a bomb. It has happened in Northern Ireland, in Iraq, in Afghanistan, in Istanbul, in Bali, at abortion clinics here in the United States. It has happened in the Moscow subway, in Madrid, and in Oklahoma City. Sometimes a political group is responsible; sometimes it is just an angry and warped individual. It happened yesterday, as well as throughout the 19th and 20th centuries.

We should by all means adopt prudent security procedures -- as Massachusetts officials did before yesterday's race -- and revise and update those procedures in light of experience. And when we do know what motivated this particular attack, we should consider if there was anything that we might have done to prevent the perpetrators from embarking on their evil course. We should be brave and honest enough to ask if this was some sort of warped response to something we had done and consider whether what we had done was appropriate or not. To ask that question in no way justifies the slaughter of innocents, but understanding a criminal's motivations might be part of making such events less likely in the future.

But we are never going to return to some sort of peaceful Arcadia where America -- or the rest of the world -- is totally immune from senseless acts of violence like this one. There is no perfect defense and there never will be. And so our larger task is to build a resilient society that comes together when these tragedies occur, understands that the ultimate danger is limited, and that refuses to bend in the face of a sudden, shocking, and cowardly attack.