They're probably not, but I've surveyed the skies and can't find any breaches, per day. What I find is it goes on forever up there. Which is strange- not that anything else around here is really normal. But we still don't know who brought us here or why, so what's to say any of it is safe?
I think patrolling makes some sort of sense. But we can't do it without buy in. I don't think it's a good idea for people to think we're just being paranoid, you know? Maybe explain it's not just about others, but possible external threats.