Ban the civillian purchases of Assault Rifles in the US, and contribute to the end of massacres!

In response to the recent Florida shooting, I strive to end the sale of firearms in the US, so all children and teachers can be safe at school. Take the Tasmania shooting in Australia. The Prime Minister banned the sale of firearms, and they haven't had a massacre since.
Perhaps the US can come out their old-fashioned ways, and wake up to reality.