Shouldn't those kind of weapons be banned in every state?<quoted text>
Not an expert on the subject, but in general:
The definition of an "assault weapon" is complex, including cosmetic features. However, the general public tends to define any semi-automatic firearms as "assault weapons", semi-automatic meaning that they can eject spent shell casings and chamber the next round without additional human action, but (as opposed to automatic firearms) only one round is fired per pull of the trigger.
There is no federal ban of "assault weapons", although some states have their own bans.
I kinda knew what they were, by the way. Just never understood why they were part of the second amendment if legal anywhere.