Nationalism is the reason empires - coercive multinational entities - are doomed to fall while nations can endure. It's been so for some 200 years and shows no signs of abating.

The most powerful force in the world is human stupidity.
A dark matter of history, so rarely taken explicitly into account.

I would think religion might trump nationalism. Religion or religious conflicts can break up and destroy nations (Iraq a recent example), but I am not aware of nations or nationalism destroying a religion. The USSR tried to destroy religion in Russia but couldn't do so. When the two are joined, their combined force is virtually impossible to defeat as the US is discovering in Afghanistan. One might have to include secular ideologies like Nazism and Communism in the religion category or as a sub category as quasi-religions. Communism+Chinese nationalism made Mao invincible. Ditto for Vietnamese nationalism. Religion has broken up Sri Lanka and British India, etc.

Historically, Professor Stephen M. Walt is right in tracing the origin of nation-states and of the idea of nationalism during the last two hundred years. Generally speaking he is right in his emphasis on the power and force of nationalism in the policies and decisions of States, but we need to look at specific instances far more closely and not reach conclusions in a hurry.
Among the specific instances that I propose on the present occasion to speak about are those relating to China, Pakistan, and India, areas that have been the subject of my study and concerns for some time. As an Indian myself I understand a few things instinctively about India and a few more about Pakistan because by origin I come from Rawalpindi. I also taught Chinese history for some years at university.
China
The empire or republic of China has been a continuous State for several millennia. It was not always as large as the present-day PRC. Many of the outlying areas became parts of the empire at different times in history and for different lengths of time. Peoples at the periphery of the empire were themselves a menace to the settled provinces of China, the historic 18 provinces. These areas – namely, Manchuria, Mongolia, Xinjiang, and Tibet – were and still are peopled by non-Han ethnic groups and were not always subject to the authority of the central Chinese government. It was a see-saw struggle or contest between frontier peoples and the Han. Eventually, the empire subdued many of these peoples and brought them into subjection to the central Chinese authority. This is not the place to go into the minutiae of Chinese history but suffice it to say that it would perhaps be an exaggeration to regard the present PRC, where the Han constitute as much as 95% of the people, as a nation. This country has brought several non-Han peoples into subordination to itself. It would be ahistorical to regard these non-Han peoples as parts of the Chinese nation. Besides, the idea of nationalism is really alien to China and its peoples, as it is to several other Oriental societies. In these societies the idea that was uppermost in the minds of people was the idea of patriotism, not nationalism which was really a parenthetic importation from the European historical experience and European and Western intellectual discourse.
Pakistan
This was an artificially created State and as we all know it began as a nation in two parts divided by more than a thousand miles of foreign territory. The very idea of Pakistan as a nation was unnatural as was the parent idea that all Muslims of the Indian subcontinent constituted a distinct nation. For one thing, these Muslims were for the most part converts from local communities and perhaps less than one per cent really came from foreign Islamic societies, like the Turks, Persians, and Mughals (the last mentioned were descended from Turks and Mongols). The few that came from outside stayed on long enough to become totally assimilated into local communities. As such, it is doing violence to the idea of family and the idea of community to think that one starts belonging to a different family or community if one converts to another religion. Not all conversions were voluntary in the first place. We have conversions to Islam in the first instance and to Christianity in much smaller numbers. It is anti-logical to assume that any who converted to Islam or Christianity started belonging to another “nation”.
The initial dispensation placed a larger number of Bengalis under the authority of a government headquartered in the western part of the country. Not many in the western part were really enthusiastic about the cultural specificities and the Bengali language of the eastern part. In fact the early leaders in the western part failed to allow even a reasonable play to regional personalities – first in the eastern part and later, when the eastern part broke away to form a separate country, the provincial personalities in the western part. That is the explanation of several of the present-day movements in many of the provinces in the western part. The central government failed to allow proper and adequate play to regional and provincial personalities, thereby making nonsense of the very idea of Pakistan as a nation. We wait to see how the future will work out.
India
The subcontinent was not always a single State in the sense of an empire, although at time very large parts of it were comprised in a single empire. At different times, empires based in the subcontinent had their authority enforced in places as far as Afghanistan in the west, Assam in the east, the entire western part, and very large parts of the south, but not all of it. For some time, perhaps a brief 60 years or so, even Ceylon was part of a south Indian empire.
It was the British that brought the whole of the subcontinent under a single authority, and even added to it the rather large area of Burma, which to be sure was never part of any India-based empire before the British. Bowing to history and ethnicity, the British government made Burma into a separate country in the later stage of their control of the subcontinent, which in a way was the right thing to do.
It would be futile to think of the Indian people as one nation, although several of India’s modern leaders, who were educated in British universities for the most part, attempted to inculcate a “nationalistic” spirit among the Indian people. In terms of ethnicity and sociology, it would be nearer the mark to think of India as a republic that comprises a population that is at once multinational, multiethnic, multilinguistic, and multireligious. There have been factors of unity as well as fissiparous tendencies in several parts of the country.
There is nothing axiomatic about how things will work out eventually but it is hopeless to think that any armed movement in India, Pakistan, or China can really succeed in breaking away from the central authority. Each of these countries is too well organized and too powerful for any province or part that may nurse ambition to break away, whether we consider it in terms of ethnicity or “nationalism”. In any case, however, religion is not an important consideration in the case of the secessionist movements in any of these countries.
Kashmir
This is an area situated at the crossroads at once of history and movements of peoples in the past. Through history it has had connections with empires and territories on all sides. It even had historical contacts with far distant empires and extensive trade relations when it was under distinguished leadership. In the modern period it became part of several empires. Finally it came under the authority of the British government and had to contend with several possibilities when independence dawned on the subcontinent in 1947.
The present-day situation is that this is an area which, or any part of which, does not really “belong” to Pakistan or India: there is really no preponderating reason why it should belong to one of them instead of the other. Constitutional and legal niceties apart, a day must come when the people of Kashmir will once again come under a single government. They have to decide whether they want to be part of India, part of Pakistan, or independent as a sovereign State. Whether they constitute a nation in the sense nationalism is being discussed here is a moot point and perhaps no answer is possible. In basic terms, every one of the characteristics that we spoke of earlier in respect of India – all the four multis – shall be found to characterize the people of Kashmir as well. Eventually they will decide what their future ought to be.
V. C. Bhutani, vineycb1@vsnl.com, Delhi, India, July 16 2011, 1415 IST

I have been thinking that nationalism is an important factor in international politics. Along with nationalism, is the force of private globalized interests that threaten or actually do undermine the concept of “nation-state”.

In many cases, these private interests certainly do not represent a broad popular base and are immune to most public accountability. They have gained great amounts of power at the center of governments while at the same time are not nationally centered, but are global. For example, at least according to the documentary, INSIDE JOB, “It’s a Wall Street government!” That “Wall Street government” has great influence all over the globe including Greece, Ireland, Italy and beyond. In many cases and times, the private interests retain more power over a nation’s destiny than a national government.

Thus, the actual holders of power are separated from the forces of nationalism.

No doubt, we can think of many complexities, but at this point, I have to wonder if the force of nationalism can overcome the structure and organizational capabilities of private interests.

Bob Spencer

The most powerful force in human affairs, as in the natural world, is inertia. The questions of when to value it, how to manage it, and when and how to overcome it are of abiding importance at every level of government.

Walt's definition of nationalism is too broad and too vague. Of course nationalism looks ubiquitous when it is defined to apply to most groups,whatever the nature of their identity.. Pakistan and India have been mentioned above as problematic. Does "nationalism" in any meaningful sense account for such large multilingual and multiethnic states?

The "Arab world" seems to suffer from a lack of nationalism: Iraq (Sunni vs. Shia), Bahrain (Sunni vs Shia), Syria (Alawis vs Sunni), Libya (Ibadi, Sunni, tribal splits). One could go on with more examples from around the world.

A lot of political science is based on bad historiography. A new book of history, Shattering Empires, by a Princeton professor, argues against this view of nationalism as the ultimate force.

ELLERVEIRA
I appreciate your questions. Let’s take up the first, the one relating to religion as the basic reason why Pakistan was made.
It would perhaps be distortion of history if we said that Hindus and Muslims were incompatible during British rule in the subcontinent. Islam made its entry in the subcontinent as early as the 8th century and continued to expand by conversion of local people in different areas. Several areas came under the rule of Muslim rulers by conquest. Some of them proceeded to make forcible conversions to Islam in areas under their control, although without doubt there were better enlightened Muslim rulers too. The rulers and the ruled did not mix socially and so the conquerors remained a class apart. But those converted from local communities had lived here for generations and continued to live peacefully with their non-Muslim neighbours. I am not suggesting that the British brought about divisions among the local people on the basis of religion, for instance: divide and rule was not an invention of the British; it was the practice of alien rulers in all ages and climes. Perhaps it will be found even in the practice of rulers like Julius Caesar.
Indian history has no record of any significant clashes between Muslims and non-Muslims of the subcontinent under the rule of any dynasty anywhere in pre-British times. Hindu-Muslim riots were recorded only during the British period, perhaps because the British were the first to introduce a whole system of record-keeping and archives, which survived British withdrawal. India is dotted with archives at the central, state, district, and court levels.
In 1947 some areas in the northwest of the subcontinent and the eastern part of the province of Bengal in the east were detached from the Dominion of India and made into a separate Dominion: to begin with both Pakistan and India were Dominions and still under the British Crown. Pakistan included the three provinces of West Punjab, North West Frontier Province, and Sind in the west and East Bengal in the east. Shortly after independence the Pakistan government annexed the princely state of Kelat, which became the kernel of the province known later on as Baluchistan. The ruler of Kelat was not given a choice: he was deposed. Baluchistan thus became a part of Pakistan by forcible annexation.
Almost on the morrow of independence Pakistan’s forces marched into the western parts of the state of Jammu and Kashmir and came in occupation of about 35% of the territory of the state. Since the state of Jammu and Kashmir was not yet part of the Dominion of India and was actually independent at that time, Indian forces did not make any move. It was only after the ruler of Kashmir acceded to the Dominion of India on October 22, 1947 that Indian forces moved into the state to defend what had by then become Indian territory. Pakistan’s forces were by then almost within sight of Srinagar and were stopped just outside it: there they have remained ever since. The rest as they say is history.
East Bengal broke away from Pakistan in December 1971 to form the new country called Bangladesh, although West Pakistan and East Bengal were both Muslim majority areas: Islam failed to keep them together.
I really wonder how strong a factor was Islam to have brought about the division of British India in 1947. It was political ambition of Muslim League leaders of the time and their intellectual pettiness that they stood out for partition. I wish there was somebody around then like Abraham Lincoln, who fought a civil war to keep his country together. If I had in my hands the making of decisions in 1947 I would have fought a civil war to avoid partition. As it is, partition did not solve any problem: it only multiplied by two every problem that British India faced earlier. Even Jinnah is said to have realized before his death that it was an error to have gone in for partition and Pakistan, but of course by then it was too late. Besides, there is no real evidence that Jinnah indeed realized that partition had been an error. As far as I am aware, Jinnah may or may not have had such a realization.
This does not show that Hindus as people and Muslims as people were separated into two countries. In fact there was no thought of moving people. It was only the riffraff of Muslim League – not senior leaders perhaps – that brought about Hindu-Muslim riots in various parts of the country, especially Punjab and Bengal, both of which too were partitioned as provinces: the new provinces were known as West Punjab and East Bengal of Pakistan and East Punjab and West Bengal of India. Some of the names were retained, others were changed. The partition did not bring about a neat separation of Hindus in India and Muslims in Pakistan. In fact Hindus and Sikhs remained in Pakistan and very large numbers of Muslims remained in India. India and Indian leaders – Congress leaders – did not accept the so-called basis of the partition, namely, making Pakistan because Muslims wanted a homeland of their own. That’s why a large of Muslims remained in India: only a small number went to Pakistan. Eventually, India adopted a secular constitution at the end of 1949 and made it effective from January 26, 1950. There is no mention in the Indian constitution of a state religion or the preference or patronage of the state for any one religion. It was only Pakistan that professedly made itself an Islamic Republic.
Bangladesh in the early years after 1971 remained secular in its orientation but after some time even Bangladesh adopted what were professedly Islamic principles, in violation of the Bangladesh constitution. Some of those Islamic features still remain in force. But it stands to reason that the people of Bangladesh, that is, East Bengal, are more Bengali than Islamic. For that matter, there is possibility that Bangladesh may swerve round to a secular dispensation in due time.
There have been communal riots and movements in India after independence, but these were aberrations and not the mainstream. Even the destruction of the Babri Masjid in Ayodhya in December 1992 and Gujarat pogrom of Muslims in February-March 1993 were overly Hindu events which were not supported by any of the mainstream political opinion in the country, although in terms of petty politics some leaders and parties may have supported those events. It is to be noted and remembered that the Gujarat chief minister was refused a visa for entry into the US.
The question of the Tamil movement in Sri Lanka (Ceylon) has to do with the kind of treatment that Tamils received from the central government. This has nothing to do with the Tamils being Hindu and the Sinhalas being Buddhist, although both are facts. Tamils profess to be fighting for achieving a homeland for themselves in the island. The Indian government has never expressed itself in favour of partition of the island into two countries. As it is, for the present the Sinhalas under the president’s leadership have got the better of the Tamils, whose EELAM has almost petrified. This has more to do with ethnicity than with religion.
V. C. Bhutani, vineycb1@vsnl.com, Delhi, India, July 17 2011, 1100 IST

because lots of nationalism arises out of conflict. Remove the opposition and nationalism tends, I think, to break down.

Just a thought, but seems to me there should be data on this somewhere. Perhaps someone should sit down and evaluate the Upsala dataset in this regard.

Einstein is quoted as saying the most powerful force in the world is compound interest. Considering our debt issues, this might prove to be more powerful than nationalism. What do I win?