Iraqi authorities arrested four armed Americans in civilian clothes in Baghdad who claimed they were there to protect Shiites heading toward Karbala. The two men and two women were reportedly carrying automatic weapons and driving a silver BMW with unregistered diplomatic plates. The Iraqis said that they found this all suspicious, since there had been no prior coordination and the law forbids such American activities without notifying the responsible authorities. The U.S. Embassy reportedly stepped in within 15 minutes of the arrest, and the four were released without charge. It isn't obvious exactly what was going on, but we can all probably guess.

Baghdad governor Salah Abd al-Razzaq told reporters that even if the group were U.S. intelligence operatives, their activities had nothing to do with Iraqi security and were a clear violation of Iraqi sovereignty. He demanded an explanation from the U.S. Embassy and a promise that it not be repeated. A diplomatic crisis seems to have been averted, but the curious episode should be a cautionary tale. Whatever really happened, this could have easily escalated into a major diplomatic showdown and a legal nightmare for the Embassy.

Expect a lot of more of these kinds of incidents in the coming days. While there hasn't been much coverage of the incident in English, it's being heavily covered in the Arab and Iraqi media. Arresting and exposing American operatives in Iraq is going to be politically popular and the local media will eat it up. A lot of ambitious political forces might find it useful to be seen on TV arresting an armed American. Armed Americans traveling around Iraq, whether security contractors or intelligence operatives, are going to be an endless source of potential crisis. And people wonder why the Pentagon staunchly opposed maintaining any U.S. military presence in Iraq without a SOFA which guaranteed immunity from prosecution for American soldiers?