TSA and the 4th Amendment

It seems there is a story daily this week about TSA abuses in airports. I began wondering at what point the 4th amendment steps in to protect you against TSA harassment. After some research, it turns out, apparently some 1973 court ruling said you have essentially no 4th amendment rights in airports. Yes unbelievably, zones exist where your unalienable rights can be suspended. It's amazing small rulings like this with potentially huge ramifications go unnoticed by the general public, and how a ruling made decades before the existence of the TSA can justify their illegal behavior. Their response, "passengers may avoid the search by electing not to fly."