[rayiner]

The 4th amendment uses flexible, context-dependent language. It prohibits "unreasonable" searches. What is unreasonable? Clearly, the framers didn't mean border searches were unreasonable, because one of the very first things they did was create customs enforcement. By virtue of mathematical necessity, those border searches have always occurred some distance in from the mathematical line representing the U.S. border.

Put differently, border searches aren't a "suspension" of "constitutional protections" but a limitation on the scope of 4th amendment rights. If you shoot someone dead in public, a police officer can arrest (i.e. seize) you and search you without a warrant. Your 4th amendment rights aren't suspended, they just don't extend to that scenario. The same thing is true at the border. Nations have a sovereign right to police who and what goes past their borders. Borders are the very things that define nations, and nations defend those borders with guns and blood. Nothing in the 4th amendment provides reason to believe that the framers intended to just throw away that ancient concept.