America's defeat in Vietnam, humiliation in Lebanon and Somalia and continuing difficulties in Iraq underscore the limits of U.S. conventional military superiority.
Great powers have often performed poorly in wars against weaker enemies waging irregular warfare – so-called small wars. Such enemies have a greater will to win because they have a greater stake in the war's outcome. In Vietnam, the Americans waged a limited war while the Vietnamese communists waged a total one. The communists sacrificed the lives of 1,100,000 soldiers to win, whereas the United States quit after losing a comparatively paltry 58,000.
Irregular foes can also employ superior strategies. In Vietnam, the communists fought a guerrilla war against a politically impatient America and a tactically inflexible American army. They denied decisive targets to U.S. firepower and wore down America's will to fight. Indeed, America's very form of government worked to the communists' strategic advantage, as democracies have limited tolerance for prolonged wars that their citizens do not regard as essential.
Another key factor in great power defeats in small wars is insurgent access to external assistance, which can reduce or even eliminate any material inferiority. External assistance may in fact be the most common enabler of insurgent success; few insurgencies win without it. French support clinched the American victory in the War of Independence, and Iranian support may yet bring about American defeat in Iraq.
Americans are at a distinct disadvantage in wars against materially weaker enemies, because they tend to separate war and politics – viewing military victory as an end in itself – and because the U.S. military is profoundly averse to counterinsurgency.
The American way of war is, as British strategist Colin S. Gray observes, apolitical, impatient, ahistorical, culturally ignorant, technology-infatuated, firepower-focused, profoundly conventional and sensitive to casualties. It is permeated by an unwillingness to accept the German war philosopher Carl von Clausewitz's dictum that war is a continuation of politics by other means. "Subordinating the political point of view to the military would be absurd," Mr. Clausewitz wrote in his classic On War, "for it is policy that creates war. Policy is the guiding intelligence and war only the instrument, not vice versa."
For most Americans, the very goal of war is military victory, which forbids them from allowing external political considerations to influence military operations. At the outset of the Korean War, General Douglas MacArthur publicly challenged President Truman to widen the war into China, in spite of the potential consequences of an open-ended war with China at a time when Europe remained defenseless against the Soviets.
Yet military victory is a beginning, not an end, because the object of war is a better peace. Approaching war as an apolitical enterprise encourages fatal inattention to the challenges of converting military wins into political ones. Insurgencies are, first and foremost, political struggles, and they cannot be defeated by military means alone. Effective counterinsurgency requires the utmost discretion in using force.
Pursuit of military victory for its own sake discourages planning for the second and by far most difficult half of wars for regime change: establishing the security conditions for successful political reconstruction. Those who propelled the United States into Iraq apparently assumed that the politics of post-Baathist Iraq would somehow fall neatly into place once the Baathists were out. Perhaps they didn't want to think about the possibility of insurgent resistance, because they recognized the Pentagon's deep antipathy to the counterinsurgency mission, an antipathy born of the failed war in Vietnam and an obsession with the technological perfection of America's post-Cold War conventional supremacy.
The Pentagon that went to war in Iraq in 2003 expecting a short, cheap and politically decisive victory had long forgotten – if indeed it had ever understood – the enduring imperatives of successful counterinsurgency, including minimal use of force, primacy of political responses, integrated civil-military operations and separation of insurgents from the population.
The result was a tardy, excessively violent and politically vacuous response to the mushrooming insurgency. U.S. action in Iraq probably created more insurgents than it removed from the battlefield, and American policy may well have doomed the endeavor from the start, because the conventional invasion force was too small to secure the country.
America's strategic culture is hostile to politically messy small wars. Counterinsurgency demands forbearance, personnel continuity, foreign language skills, cross-cultural understanding, historical knowledge, judicious force employment and civil-military integration. None of these are virtues of the American approach to war. Americans view war as a suspension of politics and think the politics will somehow sort themselves out once victory has been achieved.
All of this raises the question: Why should the United States continue to enter wars it is not very good at winning (and for which sustaining domestic political support is inherently problematic)? A more realistic policy would be to abstain from small wars of choice, and place the protection of concrete interests ahead of moral crusades to export American political values to lands that are alien to them. Such a policy would have spared the United States the agonies of Vietnam, Lebanon, Somalia and Iraq, all places where it lacked strategic interests justifying intervention.