A friend of mine recently had a brand new laptop stolen from his 'TSA checked' baggage returning Philadelphia-LHR. One can readily envisage a system whereby someone puts a small mark on any case containing 'interesting' items, so someone else can remove them. In a conversation with Philadelphia police, my friend was informed that they are prevented by the US unions, from installing CCTV in the baggage area. The theft aspect is one thing, but the security implications, that if things can be removed, then a bomb can be put in, are astonishing. TSA offerd him 50% of the value of the laptop BTW.