If you're feeling frustrated and disgusted with our stupidity in (1) allowing an Al Qaeda operative to do his best to blow up an aircraft and then (2) tormenting innocent travelers even more after the fact, this commentary by Christopher Hitchens is for you.
Or, if you really want to get mad, you might reflect on the fact that two of the leaders of Al Qaeda in Yemen - the group that apparently planned the attack - were released from Guantanamo in 2007. This Bush era decision seems to have found favor with the new administration, because it plans to repatriate at least six more Gitmo Yemenites. (This plan is really puzzling, since Defense Secretary Bob Gates is sensible and ought to know better.)
Just remember: no matter how frustrated you get, don't call Umar Farouk Abdulmutallab a 'Muslim extremist' or talk about 'radical Islam' - wouldn't want to muddy the waters with the truth!