To the leftwing I would say: Freedom isn't safe, there's always risk in freedom. You have to accept some aspects of risk and danger with freedom.
To the rightwing I would say: Tyranny and shooting people isn't a freedom, so stop selling guns to crazy people. If you can take away a felon's God-given right to vote as a citizen, then you can not sell guns to every nutcase who wants one. And if you think YOU are the nutcase they won't sell to. Maybe you shouldn't own a gun.
@quinnsentialOne high risk individuals can be put on statewide terrorism lists. However, it takes someone if authority to do that once the person is identified. Depending on how (or if) permits are granted in a state and local jurisdictions, there might not be any mechanism to even know a persons psychological status. And most mass shooters have character traits such as rage, misogyny, substance mis/use and depressive issues but not MI. Thanks for posting this. Tough topic for sure.