It’s not a warrantless search without probable cause. It’s an inspection. Land of the free, home of the brave...
That still does not negate the 4th and 5th Amendment.
Don’t answer questions, don’t allow any searches of the inside or your person, always ask, “Am I being detained or am I free to go.”
Being “uncooperative” by asserting your rights is not probable cause.
Please post an essay of not less than 5000 words comparing and contrasting the two (warrantless* search & inspection), be sure to cite your sources.
* -- The fourth amendment requires probable cause (supported by oath/affirmation) prior to issuing a warrant; therefore all warrants w/o probable cause should be nullity. (That, however, is a different topic.)
** -- "Due process and judicial process are not one and the same, particularly when it comes to national security. The Constitution guarantees due process, not judicial process." (Eric Holder)