This exchange is troubling from several different angles. 

First off, Trump does his typical dance in which he avoids questions he doesn't want to answer by giving a simplistic jingoistic response.

He is clearly uncomfortable with the question. Why?

Overall, the above exchange is kind of unnecessary since it's abundantly clear Trump is anti-liberty and anti-freedom.

Let's recall what he said should be done with Edward Snowden. From a Washington Times story in 2013:

Edward Snowden, the man at the heart of the NSA information leaks, is nothing but a "traitor" — and America ought to recreate history in dealing with him, real estate mogul Donald Trump said on a "Fox & Friends" interview.