I fear that the kid being a "political protestor" may be the screenwriters' way of saying that "not every protestor deserves harassment".
Rioting in the streets and causing roadblocks is bad enough, at a time when the President's life is under constant international threat, it could put him at risk (same goes for other government officials).
We have the right to assembly but the left tried to prevent Republicans from "assembling" at their convention in NYC to nominate their candidate. The left's free speech does not trump the right's rights.
Ah, what a twist it would be if the SoD's son, the leftist peacenik, was in cahoots with the terrorists after all? Kinda has that Nick Berg conspiracy theory flavor.