Every single decision on the right-circle is a personal choice that doesn't endanger anybody else. (With the possible exception of the armed forces - but being trained to kill is part of that line of work, no real way around that. The key point being these folks are *trained* to kill. Service members receive far, far, far more training on proper firearms usage than your average civilian.)
Now for the left-hand circle...
1. Smoking - lol who is saying that cigarettes shouldn't be legal to buy at age 18? Not any Democrat I know. You're making crap up. Total strawman.
2. Drinking - Driving drunk is a hazard to others; however, personal alcohol consumption is only potentially dangerous to oneself. Plenty of European countries allow drinking at age 18 and I think that's reasonable.
3. Gun ownership - Now we're getting somewhere. Mass shooters are almost always very young. They tend to be isolated, edgy, and poorly-socialized, problems which hopefully tend to resolve with age. Very recent case-in-point: The Uvalde shooter bought his guns, legally, very shortly after turning 18. Then he went out and shot up a school. If he'd had 3 more years to mature, he may have gotten on a better track in life and never done that.
That's the logic behind banning gun purchases until age 21 or so. Love it or hate it, it's very straightforward and based on substantial evidence.
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