There have been some lengthy threads on this in the past, some of them quite passionate.
My dh and I are a lot like you and your dh: I am not anti-gun (I own a .22 I like to shoot at targets, though I don't hunt), but I was certainly not going to allow my *children* to play-act even something so dangerous. I would have preferred early childhood out of the Nova Naturals catalog, thank you very much. I had a no-gun policy until my ds was 4, which was as long as I could hold out: my dh is from a rural area where guns were a fact of life, he grew up hunting and "shootin' stuff" and all of the typical redneck stereotype activities you can imagine. ;)
When ds was 4, he started making things into guns: biting his toast into that shape and yelling POW POW POW! I tried swords to appease the interest in weaponry, which held us out for almost six months .... but I finally consented to a Nerf gun. I will not allow anything in the house that looks real, and Nerf guns are not "real-looking" to me. There are a whole host of rules which accompany the guns/darts, and for the most part, the kids are fine about them.
I should also note that dh is a law enforcement officer to boot, so ds/dd see him strap on a duty belt every morning, complete with gun & taser. It flew under their radars until ds was 5/dd was 4, and then they started asking questions. We're big on the gun safety teaching. In our area of the country, it is a fact of life - lots of kids around here start hunting around kindergarten-age, and ds is in the minority in his class in that we have not introduced him to that yet. I'm not quite there yet.
A lot of random thoughts here (sorry), but that's my position. I'm not passionately against any type of gun-sort of thing -- to deny guns is to shortchange my kids by not providing the conversation/discussion/teaching/framework for appropriate use that I think is necessary to put guns into context in our lives - which, as we live in a rural area & dh carries one - means that they are present in our lives and just another thing we need to teach our kids about.