Most Americans seem ready to consign the Iraq war to history. They've watched tank convoys leave Baghdad, and they've heard the president underscore his campaign promise to draw down U.S. forces, leaving roughly 50,000 in the country as of Aug. 31. Moreover, Iraq and the U.S. have agreed that the remaining U.S. troops will be gone by December 2011. But history suggests that unless the U.S. is willing and able to remain committed to Iraq's security and prosperity — and Iraqis know it — the country is at risk of spiraling back into civil war.
Civil conflicts like those we have seen in Iraq since the U.S.-led invasion often recur when parties to a conflict fail to dedicate themselves to a peace process. Scholars call this the "commitment problem." If a state is without effective political institutions or professional armed forces, and if no warring faction has been able to achieve a decisive military victory, only an impartial outside power can enforce the belligerents' demobilization and political power-sharing to prevent conflict from flaring up again.
Although Iraq has made remarkable progress toward stability, the commitment problem persists. Since the January elections, Iraqi political leaders have been unable to form a government, and localized violence has reignited civilians' fears of becoming the target of attacks. Unless America is effective in its new peacekeeping role, even moderate Iraqis could lose faith in demobilization and disarmament and turn to violence.
To prevent this, the United States must demonstrate its commitment to peacekeeping by maintaining a substantial military presence in Iraq. Credible commitment requires a large number of ground troops and a demonstrated readiness to use military force decisively and quickly. The U.S. has at least a good beginning: 50,000 troops are probably adequate to the task.
Many stability operations have failed because of insufficient resources. A case in point is the United Nations' attempt to stabilize the island of Cyprus in 1964 by replacing British counterinsurgency forces with peacekeepers. Largely due to the shortage of combat troops, civilian personnel and technical expertise, U.N. forces were unable to prevent renewed civil conflict, the 1974 coup by the Cypriot National Guard or Turkey's invasion of Cyprus and the division of the island into Greek and Turkish sectors. The violence escalated into ethnic cleansing when the United Nations, facing a financial crisis, reduced its forces by roughly 70%.
If America's remaining troop numbers are likely to be adequate, its timetable is not. The United States must accept that building a sustainable peace requires years of meaningful involvement. In 1999, an international peacekeeping mission began in East Timor, after a long battle for independence. That mission is expected to continue beyond 2012. And during this effective peacekeeping and nation-building effort, the Australian-led International Stabilization Force had to take quick action to suppress a 2006 crisis that erupted in East Timor's military — an argument for maintaining U.S. troops in Iraq, close to the source of any uprising.
While the U.S. must demonstrate its strong commitment in Iraq, it must also make clear that its involvement is not unconditional. In general, an external power's leverage decreases as its stake in another country's security and prosperity increases. The deeper the U.S. involvement in South Vietnam during the Vietnam War, the less influence the United States had over the South Vietnamese government and its security forces. The reason is clear: South Vietnam recognized that because the U.S. had put so much on the line to thwart communist expansion, the Americans would not abandon the country despite its dysfunctions.
However, insufficient and inconsistent involvement can be just as bad. Between 1980 and 1992, the United States provided El Salvador assistance to fight the insurgents of the Farabundo Marti National Liberation Front. U.S. security assistance was conditional on improvements in the human rights record of the Salvadoran security forces, and economic aid was contingent on El Salvador's adoption of democratic principles. But the presence of only 55 American advisors on the ground meant, among other problems, that the U.S. conditions could not be enforced effectively.
