SELDOM HAS THE GULF between diplomatic talk and effective action been as stark as it was this week at the United Nations. On Tuesday, President Bush, speaking before the U.N. General Assembly, called on the Sudanese government to stop the killing in Darfur, reiterating Secretary of State Colin Powell’s declaration that the atrocities there constitute genocide. United Nations Secretary General Kofi Annan also condemned Khartoum for its campaign of violence. And three days earlier, the Security Council passed Resolution 1564, a toothless and watered-down warning to Sudan that sanctions might be considered should the carnage continue.

Unfortunately, Sudan’s barbarity almost certainly will continue in the absence of effective action and U.S. leadership. The failure of world nations to force Sudan to change its behavior is merely the latest reminder of a fact we should have learned since the end of the Cold War–in the Balkans, in Rwanda and in Iraq. The United Nations is slow and weak, and the United States, especially when waiting on the United Nations, is itself often too slow to act.