The U.S. is now going to arm Sunni Iraqi groups — some of the very same groups that were called “insurgents” just days ago — if those groups pledge to fight al Qaeda of Iraq. Reportedly, this strategy has proven successful in al-Anbar province and will now be tested in other Sunni strongholds.

This is an interesting development, to say the least.

At first glance, the plan seems ridiculous. The U.S. could effectively be arming both sides in a civil war. “The Daily Show” spent a lot of time Wednesday making fun of the ploy, running all kinds of footage of media talking heads saying “The enemy of my enemy is my friend.”

However, the move just might be the best strategic move the U.S. has attempted in Iraq.

As Marc Lynch argued in late summer 2006, neither the Iraqi Sunni nor Shia want to see Iraq dominated by al Qaeda.

This latest agreement between the U.S. and Sunni groups could be a sign that the Sunni want to eliminate the most radical and violent elements of the insurgency. At minimum, the Sunni likely recognize that the end of al Qaeda might mean the end of a major U.S. presence in Iraq. Most Iraqis want that.

Given the relatively small number of foreign fighters supposedly in Iraq, this mission could be more attainable than prior stated U.S. war goals.

The Shia and Kurds, who have been doing relatively well under the U.S. presence, might now receive the message that they have to get more serious about sharing power with the Sunni — and achieving more of what has been expected of them by the U.S., such as an oil revenue-sharing plan.

Recent Turkish attacks on “Kurdistan” indirectly apply the same sort of pressure. Many Kurds must think that there’s no way NATO ally Turkey would attack Kurds in Iraq without tacit U.S. approval.

Of course, without al Qaeda and the U.S., there is some chance that the country would be safe for those who want to pursue all-out Shia-Sunni civil war.

Before worrying about that too much, ask yourself this question: Is there any evidence that the U.S. is significantly constraining the potential violence?