The problem with these laws isn't that they can search you at the border. It's that they can search you within 100 miles of the border (https://en.wikipedia.org/wiki/Border_search_exception). The total number of people who live within that zone is 213 Million people, or 2/3 of the total population (https://www.aclu.org/know-your-rights/border-zone).

Seems like a generally terrible idea. Why this cannot be one day changed to 200 miles on a whim?