Aldon Smith -- Not On TSA Watch List ... 'It's For Terrorists, Not Idiots'

Aldon Smith is NOT on the TSA's official "No Fly List" after his false bomb arrest -- with one law enforcement source telling us, "The no-fly list is for terrorists, not idiots."

We broke the story ... Smith was busted at LAX last weekend after allegedly telling TSA agents he had a bomb. Of course, he wasn't REALLY carrying an explosive device and was arrested on site.

For the record, Aldon has not yet been charged with a crime -- but if prosecutors do decide to go forward with a case ... he could face up to a year behind bars and a substantial fine.