The exercise of force by great powers should be classified according to the category of foreign actor being dealt with. For instance, when dealing with non-state actors, the deployment of force is an exercise of ‘pacification’. The counterpart is of course guerrilla warfare or insurgency. It is the only available option to security actors who are too weak to raise conventional armies. The line between conventional armies and rebel militias is murky. The rebel militia will, as soon as the state relinquishes power, become a ‘state actor’. The important point is that pacification is the natural state of an empire at the periphery: only in exceptional circumstances does the territorial control exercised by an imperial Metropole at the periphery fail to elicit armed resistance. The Romans, the British, the Mughals, and so on, were constantly engaged in pacification operations in remote margins of their empire. When the imperial Metropole decays and its ability to impose its will weakens, unrest spreads in the periphery, and rebels gain ground. If the empire collapses due to internal decay, therefore, it looks as if it had been brought down by ‘barbarians’. For instance, Max Boot glowingly talks about “their consistent ability, ever since the barbarian assaults on Rome, to humble the world’s greatest empires.” This is an optical illusion.
Another category of the use of military coercion is with regards to weak states that are essentially defenseless against great powers. The problem of resistance or rather intemperance of such weak states is a minor irritant to great powers. One that can be swiftly converted into one of pacification by means of occupation, but it is more common to replace the intemperate sovereign with a puppet. This is properly understood to be an exercise of ‘gunboat diplomacy’, although it need not involve sea power at all. The point is that the sovereignty of the weak is a matter of choice of great powers: sooner or later such states will be either absorbed by a stronger neighbor, fall into the sphere of influence of a stronger power, or serve as buffers between two powers. The use of military force is such circumstances is a ‘police operation’. There are numerous such operations in every given year and only someone totally ignorant of international relations would regard them as anything but routine. The strong will demand obedience and the weak must submit, such is the law of the jungle.
A third category of military coercion is with regard to what may be deemed to be minor or regional powers. There are many regions in the world where the distribution of war potential allows for the creation of regional balance of power systems. That is, regional security complexes. Such subsystems are fundamentally different from the international balance of power system due to the simple fact that they do not share the most important characteristic of the latter. Namely, they are not characterized by anarchy. Thus, neorealism does not apply unless the system is totally isolated and every power is left to its own devices. In fact, the predominant form of balancing of regional powers is to seek great power patrons. This has been amply documented. The reason is obvious: the value of an alliance with a great power is more than what may be obtained by internal efforts or regional alliances.
In this mezzanine floor of international relations, military coercion takes the form of a judicious mixture of ‘gunboat diplomacy’ and balancing. Great powers will seek regional allies (and increase support for already existing ones) to contain and balance a regional power. Moreover, they will seek military bases and make efforts to bring power to bear in a region in case of a confrontation. Coercive diplomacy is preferred to large-scale military action for the good reason that it offers ‘more bang for the buck’. Great powers prefer to use ‘carrots and sticks’ to obtain diplomatic concessions from regional powers, instead of outright invasion and occupation because the costs of pacification are unbounded and uncertain. For instance, the United States can at a time of its choosing invade and depose the Islamic regime. However, any reasonable cost-benefit analysis reveals that it is better off using the threat of force, covert action, and economic warfare to secure Iran’s obedience. The costs of such a policy are reasonable, and more importantly, predictable. The costs of invading and occupying Iran might exceed those of the adventure in Iraq which has been estimated to be upwards of $3 trillion as of 2008. That number is approximately equal to the size of the German economy, the industrial powerhouse of Europe.
The Iraq debacle bears witness to the categorical misjudgment of the Bush White House. They thought they were dealing with the second category: a minor irritant that could be removed and the problem transformed to one of pacification, furthermore, that pacification itself would not be too costly and the Americans could leave an obedient substitute to Saddam without a decade long campaign. In fact, they were dealing with a regional power which served American interests in the regional balance of power in the Persian Gulf. This is immediate from the strategic effects of the Iraq debacle: the removal of the Iraqi pole from the regional calculus means that the United States is now required to expend significantly more energy to balance a relatively stronger Iran. Moreover, it has made the US more dependent on Saudi Arabia, increased the bargaining power of the latter, and reduced US’ leverage in the region. The smaller Arab Gulf states have increasingly come under the Saudi sphere of influence, as witnessed by the events in Bahrain.
The fourth and most important category of coercive diplomacy is vis-à-vis other great powers. That is, Weltpolitik. This requires a finely calibrated and nuanced approach where credibility is most important. Here, neorealism applies with full force since the costs of mistakes are infinitely higher: the very survival of the great power is at stake. Great power statesmen need to calculate the true balance of power and conduct diplomacy in light of that knowledge. Disagreements and uncertainly about the balance of forces increase the probability of great power conflict. Stability can persist for long periods if there is little disagreement about the balance of power. Periods when the balance is shifting rapidly are the most dangerous since rising great powers are eager to transform the international order in their favor faster than established great powers would prefer. Limited trials of strength are almost unavoidable, since otherwise disagreements over the balance of power persist.
In the years preceding the First World War, the only way Germany could’ve been dissuaded from war was if Great Britain made it absolutely clear that she would not allow Germany to occupy Belgium and destroy French power. German policymakers would not have gone to war if they did not see an opportunity to knock France out of the war before Britain could mobilize on the continent: otherwise German hegemony on the continent would then be a fait accompli for Britain. Fifty million soldiers – an entire generation of young men in Europe – had to die for Great Britain’s diplomatic blunder.
Coming to the present, a root cause of the Sino-Japanese islands conflict is uncertainty over American intentions. In 1996, State Department officials essentially declared that the United States maintains a position of “neutrality” with regard to the islands. These islands were annexed by Japan when it crushed China in the Sino-Japanese war of 1895. After the Second World War, they were used a firing range by the Americans. In 1972, they were handed back for Japan to “administer”. Whether or not America’s treaty obligation to protect Japan applies to these islands has been a matter of much controversy. The current spat has its origins in Secretary of State Clinton’s recent remark that the treaty did, in fact, apply. It is pretty clear that the United States would not allow any significant Chinese military action against Japan. However, it is also clear that it will not go to war with China if the latter downed a couple of Japanese fighter jets. China knows this. Hence, all the belligerence.
This is not a diplomatic failure of the Obama White House: there is a real commitment problem for the United States. It makes no sense to trigger a high-cost confrontation with China over a collection of islands that are of no strategic significance whatsoever. However, unambiguously declaring that they are indeed under US protection means that if China were to occupy them tomorrow, the US would face the unpleasant choice of losing credibility or embarking on a confrontation that it does not want. The first would tempt China further by implying that the United States may in fact renege on its security commitments in Asia. The latter raises the possibility of an all out great power war. On the other hand, loudly declaring US’ neutrality on the matter makes a Sino-Japanese conflict over the islands much more likely since China would see a significant gain in international status by means of coercive diplomacy vis-à-vis Japan. US’ optimal strategy is therefore maintaining ambiguity about its intentions: the possibility of a US intervention serves to dissuade Chinese adventurism and the plausible deniability of the US commitment solves the credibility problem.
To the clear eyed realist, it’s obvious that is it time for China to coerce Japan into relinquishing exclusive control of the islands. But in the final calculus, even a theory as powerful as neorealism cannot explain everything in international power politics: statesmen often fail to seize the moment, sometimes spectacularly. [Still waiting for a scholar to take up research into the German General Staff’s thinking in 1905.] That being said, the international arena is a tough neighborhood. You don’t get to complain if you get muscled out because you failed to close the deal.
 Walt, Stephen M. The Origins of Alliances. Ithaca: Cornell UP, 1987. Print.
 Stiglitz, Joseph E., and Linda Bilmes. The Three Trillion Dollar War: The True Cost of the Iraq Conflict. New York: W.W. Norton, 2008. Print.