Cool, so only criminals who are slightly dedicated to breaking the law get guns and no one else. Got it.

They are highly effective at ensuring that people who do not break laws cannot get guns easily.

The JetBlue pilot has no idea what the other crew was doing. The military flies due regard all the time and when they do, it is on them to deconflict with traffic. The JetBlue pilot might have been surprised by them but they almost certainly weren’t surprised by JetBlue and would have deviated if it actually got close.

Most of the world doesn’t have decent primary radar, especially out over international waters like where this occurred. Likely just a low frequency radar that can say “yup, there’s something out there” but not “he is right there.” The world works on transponders.

So they were 3-ish, maybe 5 miles away with altitude separation over international water? That’s actually fairly routine.