The ACLU has filed suit against the TSA claiming they are:
…subjecting innocent Americans to unreasonable searches and detentions that violate the Constitution, according to a lawsuit filed today by the American Civil Liberties Union. The ACLU filed the complaint on behalf of a traveler who was illegally detained and harassed by TSA agents at the airport for carrying approximately $4,700 in cash.
The way I see it any search by the government without a warrant is unreasonable. When it was the FAA requiring the airlines to do the searches it was questionable at best. But as soon as it was a government entity doing the searches it was way over the line.
What the TSA is doing isn’t nearly enough but it’s far better to get a small win that a big loose in the courts and for their efforts in trying to make that happen I applaud them.