Earlier quoted context omitted.
Doesn't the 5th amendment make those questions impossible to answer? (If you plead the 5th on them, you're.. probably a terrorist...)
The constitution protect non citizens too?
If you are a non-citizen living here, you'll generally enjoy most of the protections of the constitution and laws. If you are sitting there at customs just visiting, there are a lot of those protections that simply don't apply. Of course, some of those protections don't apply to citizens at these places either, though they play out a bit differently.