First, they are not trying to search everyone.
Secondly, a search to prevent the introduction of weapons aboard aircraft is not unreasonable.
Third, you have no constitutionally guaranteed right to board an aircraft. You have to meet certain reasonable criteria. You have to have a ticket. You have to be clothed. You have to be free of obvious dangerous communicable diseases. You have to be willing to not operate certain electronic equipment. You have to be willing to be searched in some way, electronic or otherwise, to ensure you do not have a weapon.
It's like accepting a driver's license and driving a car is a consent to a test for alcohol or a customs search a condition for entry into the country.
P.S. This is all very settled law.
Wrong, we have the contitutional right to do whatever we please as long as it doesn't hurt other people. Once we buy a ticket we have the right to board the aircraft. Searching people who are not likely to have a weapon, and, BTW, not allowing weapons is also a violation of my rights, is unreasonable. Searching rah heads on the other hand, due to their history of killing people and blowing things up, is reasonable. It is a rights issue and TSA should be abandoned. Israel doesn't do all this intrusive BS and they have no problems on their planes. Why do you suppose that is?