Handguns and such are not an effective defence against an invading force with tanks and overwhelming firepower. So clearly getting rid of any guns is the rational thing to do in this kind of situation.

On the other hand just because there aren't any guns doesn't mean that you aren't still quite likely to get shot. As on Bloody Sunday, and on numerous other occasions, in all kinds of places, including Israel and Palestine. (And in those cases it is pretty common for guns to turn up conveniently after the event.)

One other thing, guns is not the best way to resist invaders in these kind of circumstances - but just because people are carrying them and using them does not mean they are "terrorists".