As I have been saying for years current airport security doesn't and probably can't possibly work. Here are some other peoples thoughts on the topic:

• New Airline Security Rules (be sure and read the comments)
• Threat modeling airplane explosive detection
• Bruce Schneier points out knives and guns are built in prisons so how can we hope to keep them off of airplanes?
• Gaping holes in airport security

It's time to investigate alternatives. Even scrapping the existing system entirely and taking all that money and investing it in intelligence and police work would be an improvement.