9mm vs .45 ACP for self-defense in 2026 - is the debate over?

Honestly, modern ammo settled most of this. Today's premium 9mm hollow points (Federal HST, Speer Gold Dot, Winchester Ranger) expand and penetrate to the same FBI standard as .45. So you're trading a slightly bigger hole for meaningfully more capacity, softer recoil, faster follow-up shots, and cheaper practice ammo. For the vast majority of defensive shooters, 9mm wins on the things that actually matter — hits on target under stress. .45 isn't wrong, and if you shoot it better, carry it. But the old "9mm is a poodle-shooter" line is a relic.