What defines an assault weapon?

Aren’t all weapons used for assault? I suppose there is such a thing as a defensive weapon but being by nature a weapon when it is actually being deployed it is assaulting. It seems to me the term assault weapon is simply an invented term for propaganda. You can argue it’s exceeding a rate of fire threshold that elevates a firearm to the assault category but revolvers can be fired at up to a rate of 480 rounds per minute. A bolt action rifle is a poor self defense choice especially against multiple attackers.

Will limiting magazine capacities make us safer? Criminals don’t care so now they will have gained an advantage. What do you think?