Borders (and airports) are already a constitutional twilight zone. Just to get into (or sometimes out of) one I have to go through an X-ray scanner or manual gr

Borders (and airports) are already a constitutional twilight zone. Just to get into (or sometimes out of) one I have to go through an X-ray scanner or manual groping that on its face would violate the Fourth Amendment. But at the same time, nobody is forcing me to go there.