This month marked the fourth anniversary of the invasion of Iraq. To the surprise of virtually all the war's supporters, coalition forces are still present in Iraq. They are working to stabilize a country that appears to be on the brink of civil war. The continuing chaos and ever-growing number of fatalities are reminders of the need for patience in tackling difficult international problems. Iraq is sad proof of the need for humility in foreign policy.

The invasion of Iraq proceeded as planned. A relatively small invasion force managed to steamroll Saddam Hussein's army, which dissolved after showing no stomach for a fight. Coalition forces were greeted as liberators -- the image of jubilant Iraqis toppling a statue of Hussein and pounding it with sledgehammers is iconic. Hussein fled, along with his government.

The impact of those initial successes quickly faded. The chaos and looting that followed the invasion was dismissed by then U.S. Secretary of Defense Donald Rumsfeld as the inevitable "stuff that happens" when a long-suppressed people are liberated. But when the suspected weapons of mass destruction were not found, it became clear that they never existed.