Imagine a country that doesn't have easy access to weapons. If you want real results look at what they did in Australia. They had a similar gun culture and they were able to implement real changes and got real results.
Republicans want to blame video games, a lack of prayer and mental health. As I said above, Patrick Crusius wasn't insane neither was the Pittsburgh Synagogue shooter nor the guy that shot up the Mosque in California or the MAGA bomber that got 20 years today. The common thread is that all of these guys were conservatives that were radicalized by President Trump, Fox News and the rest of the Conservative media. No amount of mental health care is going to cure a political terrorist or even a voracious nonviolent consumer of this type of propaganda. If someone like Doc hears from Trump the Mexicans are invading and infesting America, he literally believes it is true. If anyone tries to point out the fallacy in his thinking, he screams liberal liar, fake news and you hate Trump. If someone like Patrick Crusius hears from Trump that Mexicans are invading and infesting America, he buys an assault rifle to "send them back".
The other thing is Republicans always talk about mental healthcare after these things but never follow through when they find out how much adequate mental healthcare costs. It might mean they would have to tax the rich or corporations to pay for it. So, yeah, gun violence in Chicago isn't going to make the news as long as we have easy access to guns. Gun violence in big cities has been accepted as normal. I suspect mass shootings will soon be accepted as the new normal.