1. Mass shootings are <1% of the murder rate, and murder is <1% of the death rate. Getting wound up about mass shootings is as dumb as getting wound up about terrorism. They're both very small in relation to how much people freak out.
2. We already have lots of gun control. Especially in places like California, where the killer bought most of his guns legally and passed a background check.

3. Bump stocks were the real problem. Even the NRA is open to restricting bump stocks. Let's do that.

4. Let's not go overboard with the Australian solution. Australia's murder rate almost halved from 1990 to 2015, and people erroneously give the buyback credit for that, but in that same 25 year time span the US murder rate went down even more (from 9.4 to 4.5 per 100,000) The murder rate went down everywhere in that time frame due to banning leaded gasoline that causes brain damage. Also due to some smaller factors (more abortion, better software for predictive policing).