Ban assault weapons completely. Make the sale and/or distribution of all weapons and ammunition illegal on the internet.
Why is this important?
At what point do Americans stop being cowboys and start saying "We need to lay down our weapons and start acting like civilized people?" The Second Amendment needs to evolve. No other "First World" nation allows their citizens to be endangered by one special interest group, such as the NRA. Ban assault weapons and get all gun sales off the internet.