Since the Pants Bomber thankfully failed to blow up Nortwest Airlines Flight 253 on Christmas Day, the United States has taken a long, hard look at the security failures that allowed him onto the plane -- particularly given that Umar Farouk Abdulmutallab's own father, a prominent Nigerian banker, had alerted U.S. authorities to his 23-year-old son's radicalization. Increasingly within Washington, there are calls for heads to roll. So, a straw poll: Who's it going to be?

1. Secretary of Homeland Security Janet Napolitano. In a epic foot-in-mouth moment, she said the "system worked," just after the attack. 
2. Michael Leiter, the director of the National Counter-Terrorism Center. His agency failed to analyze the intelligence that might have stopped Abdulmutallab before he got on the plane. Today, the New York Daily News ran an editorial calling for his firing, noting that he did not return from vacation when the news broke on Christmas Day. It turns out that is untrue, and wagons are circling.
3. The director of the Transportation Security Administration. Alas, the position is unfilled, thanks to Sen. Jim DeMint. The conservative senator is holding up security expert Errol Southers' nomination over concerns he might allow TSA employees to unionize.