I respectfully disagree, I don't think it's a dodge to believe it's a primarily a mental health issue. But you are entitled to your views as are others. God BlessFirst, let me say I'm sorry to hear about your wife, dementia is a terrible thing for everyone involved.
Back to the topic, trying to prevent other tragedies. As I pointed out before a purely mental health approach would be cumbersome, expensive and inefficient. Alzheimer patients do not, as a rule, commit mass murder. Many on the Right cry out "Mental Health" when these things happen. It's a dodge, a deflection. The very simple fact is that these mass shooting occur because of the nexus between mental illness and "assault weapons". Both are required, neither one alone produce these tragedies. No need to screen the entire population, only those who wish to purchase these weapons need to undergo strict scrutiny. Nobody else. If a waterfowler wants to go to a store and buy an SBE III, no problem. If a big game hunter wants to buy a bolt gun, feel free. If a pimply-faced 19 yo kid wants to buy an AR, pay attention. FBI background check. Home interview by local LEO, including anybody who lives in the home. Guarantee safe storage insofar as possible. Pay the $200 fee. These measures alone would likely prevent these people from even trying to make a purchase. One alternative is a ban, which didn't work before and there's no reason to think it will work now. To have any chance it would have to include guns in circulation, and that is not going to happen. Another is to say nothing can be done, maintain the status quo. In which case the shootings will continue unabated, so brush up on your "Thoughts and Prayers" spiel. The last option is to come up with something better than the above alternatives, and as shown on this thread, there's no interest in doing so.