Well there's a difference between an Assault Rifle and an "Assault Weapon". One is real, the other is a made up buzz term designed to stir up emotions of the willfully ignorant.

An Assault Rifle, by definition, is a fully automatic, medium sized/weight rifle designed to fire an intermediate sized cartridge with moderate accuracy out to 150 yards (In other words, you literally have to be able to hit the broad side of a barn with it at 150 yards). The original AR15/Colt SP1, meets this definition, as it was designed from the get go by Stoner to compete in the Army trials to replace the M14 as the main infantry rifle of the US Army. However this only applies to the OG AR15/Colt SP1. All civilian derivatives are honestly closer to the definition of a DMR.

An "Assault Weapon" doesn't exist. It's a fake term based on cosmetic features that appear "scary" to ignorant sheeple who think that because a gun in more ergonomic it makes it a "weapon of war". Completely ignoring all of the "weapons of war" that are now considered hunting rifles by the common man. EG. M1 Garand, literally any Mauser based bolt action, pretty much every lever action Winchester makes, Trapdoor Springfield Replicas, LITERALLY EVERY MILSURP GUN ever sold on the civilian secondary market, etc.