On: Airport security in America discovered more than seven guns per day in 2015

[fche]

And the number of shootings on board airplanes has been ... zero.

[dawnbreez → fche]

The implicit danger is that someone will fly to another part of the world and start shooting there.

[hga → dawnbreez]

And why would this be any more danger than of him using it while there?

Note that if declared, it's legal to transport unloaded in checked baggage in the US, and unless things have drastically changed the airline etc. isn't going to wonder if possession is legal for you at your destination.