Part 1 of the Christmas Bombing attempt is the lack of proper screening in airports. Part of the problem is that there aren't strong international standards for airline security. The TSA puts out a series of minimum guidelines, and doesn't accept people who come from countries that refuse to abide by it, but the TSA and Israel have stronger guidelines -- but those stronger guidelines are pointless because other countries don't hold to those stronger guidelines.
Part 2 of the Christmas bombing attempt, the one that really got this for me. It's this little article about Yemen. Projected unemployment of 70%? 45% underage? This is a shitty country, and shitty countries breed terrorists. And terrorists cross border. Because Yemen can't hold up its own people, we ourselves are at greater risk. One day, the social programs we rely on here in the US to help maintain order and relieve suffering (establish justice and promote the general welfare... oh, and ensure domestic tranquility) are going to have to spread to the rest of the world, or this will keep happening.