To be fair Matt, it’s the military that sacrifices their lives when called upon not the general populous — there hasn’t been a conscript army from Europe sent abroad since WW2; in the US, not since the 60's/70's. Here in the UK we have a military that does the things you describe as well so we don’t require the US military to sacrifice themselves on our behalf. My father, and my father-in-law, were both in the RAF and both saw action in their time.
We are not giving up our guns because we don’t have them to give up. After Dunblane, handguns were banned: there was a lot of hand-wringing from people who said one lone person shouldn’t spoil it for others but our Govt did the right thing: there’s no reason for anyone to own one of these things on a general basis.
Obviously, for farming purposes and sporting purposes guns are bought and owned. These are subject to background checks which includes being clear on how they will be stored and secured. My brother, in trying for a shotgun license, ended up with extended background checks purely because he was born in Singapore (on the RAF base) as a result of my father’s posting there. Many guns owned for sporting purposes are kept at the gun club, although that may be because we don’t have a cultural history of hunting (with guns.)
Only you can decide how safe your kids are around loaded guns. Personally, I don’t think it’s macho for them to see their father on the ground, bleeding out because he’s been taken down and I’m not convinced, in that scenario, that their immediate reaction to such violence would be to perpetuate it: in any case, they’d have to be standing there gun in hand, pointing at the perp otherwise the likely result is their bloody death before they got to it. If it was me, I wouldn’t be hanging around with my kids, the lot of us would be out of there. Still, that’s your country’s issue because the chances of it happening here are pretty slight (almost, but not, non-existent) — we don’t have general access to firearms and even criminals are wary of bringing shooters to the match. There’s a bigger knife problem here but that is legislated against even carrying in public and sentences can be severe.
Which sort of addresses your final point: our criminals don’t have ready access to guns so it is a much, much safer country — all the stats prove that countries who have legislated on gun control are much safer than the US.