by Michael Dorf
One of the seemingly stranger possible outcomes of the ISIS advance in Iraq is an alliance between the United States and Iran to stabilize Iraq (as discussed here). But the outcome only seems strange. Here I'll very briefly explain why.
From 1990, when the U.S. decided to confront Saddam Hussein's Iraq for its invasion of Kuwait, the U.S. has been in an on-again-off-again informal alliance with Iran. President George H.W. Bush launched Operation Desert Shield less than two years after the ceasefire that ended the Iran-Iraq War, at a time when Iran and Iraq remained bitter antagonists. The first Gulf War, by weakening Saddam, and the second Gulf War, by removing him from power and replacing the Sunni-dominated Baath Party with a Shiite-dominated government, did a great deal to further the regional interests of Iran. Promoting Iranian interests can hardly have been the purpose of the U.S. in going to war in Iraq, but that was its foreseeable and actual consequence.
To be sure, it was easy to miss the de facto alliance between the U.S. and Iran in Iraq because, soon after the fall of Saddam, Iran began to give support to Shiite militias that were hostile to the U.S. occupation. But that only shows that the Iranians believed that once the U.S. had removed Saddam, we had served our, that is to say, their, purpose.
Now it is one thing to take note of the fact that nations that may be antagonists in general sometimes have shared interests or unwittingly serve each other's aims. It is something else to say that a nation will form an actual alliance with a seemingly implacable ideological foe. Yet that too is something that the U.S. has done at least once before, during the Second World War. At no time during World War II did U.S. cooperation with the Soviet Union reflect anything more than the shared belief that Nazism posed an existential threat to both countries.
Likewise now in Iraq, limited U.S.-Iranian cooperation or coordination in supporting the Iraqi government against ISIS would not necessarily herald any broader or longer-term cooperation. Recall that while the first strategic meeting of Churchill, Roosevelt, and Stalin (in late 1943 in Tehran, interestingly enough) focused mostly on coordinating the fight against Hitler, by the Yalta Conference a little over a year later, the U.S. and U.K. were already jostling with the U.S.S.R. for dominance in post-war Europe. Alliances of convenience tend to last only so long as they are mutually convenient.
Although I have given only one example of an ideologically awkward alliance of convenience with the United States, depending on how one defines terms, there are countless others. During the Cold War and even today, the U.S. worked with and continues to work with non-democratic countries that advance their own interests, often interests antagonistic to ours.
Meanwhile, broadening our focus still further, we can see numerous instances of fierce rivals temporarily putting aside their differences to fight the common enemy. Virtually every major revolution includes this dynamic, including: the 1789 French Revolution followed by the Jacobin Terror turning on Girondists; the 1917 Russian Revolution followed by White versus Red Civil War; Chinese resistance to Japanese occupation followed by the civil war pitting the Kuomintang versus Communists; the somewhat broad-based Iranian Revolution followed by the consolidation of power by the Khomeini faction; and most recently, the same pattern in Egypt, followed by a quick restoration (in all but name) of the ancien regime.
The last 225 years show how ideological enemies can come together to bring down a regime before turning on one another. There is no reason to think that the phenomenon cannot operate in reverse: ideological enemies coming together to prop up a regime before turning back on one another.