"Peacekeeping Doesn't Work."
It does now. The early 1990s were boom years for the blue helmets, with 15 new U.N. peacekeeping missions launched from 1991 to 1993 -- as many as in the U.N.'s entire history up to that point. The period was also host to peacekeeping's most spectacular failures. In Somalia, the U.N. arrived on a mission to alleviate starvation only to become embroiled in a civil war, and it quickly pulled out after 18 American soldiers died in a 1993 raid. In Rwanda in 1994, a weak U.N. force with no support from the Security Council completely failed to stop a genocide that killed more than half a million people. In Bosnia, the U.N. declared "safe areas" for civilians, but then stood by when Serbian forces overran one such area, Srebrenica, and executed more than 7,000 men and boys. (There were peacekeeping successes, too, such as in Namibia and Mozambique, but people tend to forget about them.)
In response, the United Nations commissioned a report in 2000, overseen by veteran diplomat Lakhdar Brahimi, examining how the organization's efforts had gone wrong. By then the U.N. had scaled back peacekeeping personnel by 80 percent worldwide, but as it expanded again the U.N. adapted to lessons learned. It strengthened planning and logistics capabilities and began deploying more heavily armed forces able to wade into battle if necessary. As a result, the 15 missions and 100,000 U.N. peacekeepers deployed worldwide today are meeting with far greater success than their predecessors.
Overall, the presence of peacekeepers has been shown to significantly reduce the likelihood of a war's reigniting after a cease-fire agreement. In the 1990s, about half of all cease-fires broke down, but in the past decade the figure has dropped to 12 percent. And though the U.N.'s status as a perennial punching bag in American politics suggests otherwise, these efforts are quite popular: In a 2007 survey, 79 percent of Americans favored strengthening the U.N. That's not to say there isn't room for improvement -- there's plenty. But the U.N. has done a lot of good around the world in containing war.