Years ago I flew out of Amsterdam to SF. When we arrived we were all herded into a small room at the SF airport, and our baggage was there when we got there. There were no chairs in that room and we were forced to stand around for about two hours and nothing was happening, except that we were not allowed to leave. Finally some customs officers showed up and began painstakingly searching every bag in the room. Once your bags had been searched you were able to leave.
Don’t know what was going on. Never found out. But, boy was I furious. I missed a connecting flight and also my pickup limo. It was outrageous. At the time I assumed they were looking for drugs, but now I’m not so sure.
One strategy with the bags is that if the person is not wanting to be a “suicide” bomber, locking him in a room with the bags for a few hours might provoke some telltale behavior on the bomber’s part.
That’s one of the reasons in Germany your luggage was not put on the plane until you got on the plane and could not get off. At least deterred the hit-and-run terrorists.