As former Bush administration strategist Meghan O’Sullivan recently wrote in The Post, Iraq has fallen well short of both American and Iraqi expectations. The pain and cost of that war are some of the reasons the United States and its allies have sworn off intervention in Syria and why the Obama administration made a half-hearted effort in Libya.

Iraq, however, looks a lot like what Syria, and much of the rest of the Arab Middle East, might hope to be. Its vicious dictator and his family are gone, as is the rule by a sectarian minority that required perpetual repression. The quasi-civil war that raged five years ago is dormant, and Iraq’s multiple sects manage their differences through democratic votes and sometimes excruciating but workable negotiations. Though spectacular attacks still win headlines, fewer people have died violently this year in Iraq than in Mexico — or Syria.

Just as significantly, Iraq remains an ally of the United States, an enemy of al-Qaeda and a force for relative good in the Middle East. It is buying $12 billion in U.S. weapons and has requested that an American training force remain in the country next year. It recently helped get two U.S. citizens out of prison in Iran.

All of this happened because the United States invaded the country.