That's absolutely true. You can be denied your right to travel for cause. Bizarre behavior, drunkenness, overt belligerence and disorderly conduct among other things, hav gotten people of all races kicked off planes, trains, and buses, as well as diners, bars, and sports arenas.

But to subject Arab Americans or Muslim Americans to additional scrutiny on the basis of their origin without a belief, supported by specific knowledge, that they pose a likelihood of mayhem is constitutionally impermissible.

While it may be de iure unconstitutional, I'm sure racial, ethnic or religious profiling exists on a de facto basis among many law enforcement and governmental agencies.