Yesterday's revelation of a new al Qaeda terrorist plot is a reminder that the group's Yemen-based franchise, al Qaeda in the Arabian Peninsula (AQAP), is strong and ready to kill Americans.

Seized as it was being transported to the suicide bomber, the new underwear bomb was designed to elude U.S. airport scanners and was likely aimed at a U.S.-bound aircraft. Timed to commemorate the anniversary of Osama bin Laden's death, the plot was well underway even as American officials denied there were any planned attacks.

The death of Osama bin Laden may have struck at the core of al Qaeda, but its Yemen-based franchise is alive and well. Even the killing of AQAP's American-born leader, Anwar al Awlaki, has failed to end the group's transnational operations. The bottom line is that the al Qaeda franchise is stronger than it was in 2009.

Last year, AQAP took advantage of the widespread unrest in Yemen to secure and expand its area of control. It launched a territorial offensive run through its insurgent arm, Ansar al Sharia, in March 2011. The result is a swath of territory in south Yemen connected to historical sanctuaries running up to the Saudi Arabian border that has vastly expanded the area in which AQAP members can travel. Recruiting efforts have paid off as well. Three years ago, AQAP consisted of a network of a few hundred individuals. Today, estimates range to over a thousand militants in Yemen.