In his seven hours long and counting filibuster of John Brennan's nomination to head the CIA, Senator Rand Paul (R-Ky.) brought up his failed attempt at revoking the authorization of the use of military force in Iraq after Barack Obama failed to postpone the end of the war. Paul tried to revoke the authorization by amendment to the National Defense Authorization Act in 2011—the amendment failed with only 30 yes votes (only three Republicans joined Paul; Jim DeMint, Dean Heller, and Olympia Snowe). Less than a year later, the fact that that authorization for military force remained in effect helped the administration redeploy military (special ops) forces to Iraq without controversy or, for that matter, coverage. Spotted by the Nation, in the fifteenth paragraph of a contemporaneous New York Times article (below the digital fold):

Iraq and the United States are negotiating an agreement that could result in the return of small units of American soldiers to Iraq on training missions. At the request of the Iraqi government, according to General Caslen, a unit of Army Special Operations soldiers was recently deployed to Iraq to advise on counterterrorism and help with intelligence.

The last U.S. commander in Iraq before the troop withdrawal told a Senate committee last month that the situation in Iraq remains "fragile." As Rand Paul reminded us today, the authorization of military force is still in effect, so the door to war remains always open.