> Why couldn't it? Metal of X thickness = stopped bullet. Not exactly a hard problem to solve for. I mean... talking about real-world guns, technology already

> Why couldn't it? Metal of X thickness = stopped bullet. Not exactly a hard problem to solve for. I mean... talking about real-world guns, technology already evolved to the point that doesn't really work anymore? Modern body armor isn't about metal of X thickness, it's about material science and spreading out the impacts, and even then it can only sustain a few direct hits. Like, the asymmetry between offense and defense feels pretty obvious here. You can carry a handgun in a small bag. Bulletproof armor is heavy, cumbersome, conspicuous, etc.