What will they do when someday our phones are chips in our brains? "Please sir, I need to cut your head off for a bit". Eventually technology will make it almost impossible to do a real border search.
They'll require root access as a condition of travel.
(A variant of this idea appears, as a throwaway peripheral detail, in the excellent s01e03 episode of the TV series 'Black Mirror', 'The Entire History of You'... which according to Wikipedia has been optioned by Robert Downey Jr. as a potential film.)
