The level of fear instilled into the population is wildly disconnected from the realities of risk and we've known this for decades. Whether it's the security theater at the airport, modern day duck-and-cover, or whatever the 6pm news is scaring old people with this week; the line of reasoning that goes something like "we taught people to fear risk X, the way to alleviate the fear is to reduce the likelihood of X" is the most asinine bullshit in the world.
The way to alleviate the fear is through education and turning off the dramatic, need FUD (Fear, Uncertainty, and Doubt) to sell things, "news".
The US was a scary place after 9/11. I'm sure a lot of money was wasted in domestic security that didn't do anything, but I'm glad we made an effort to reduce the likelihood of future terrorist attacks rather than just reinforcing how incredibly rare they are.
We can't stop terrorism or mass shootings but we should try to make it as difficult as possible even if they are rare events.
I'm going to preface this by saying I have no opinion on gun control.
Gang members don't live in neighborhoods inhabited exclusively by other gang members (I doubt they make up the majority in any neighborhood). The people who live in these neighborhoods never consented to this, and it's much harder for them to move than to avoid public areas so imho gang violence is just as bad if not worst than any other type of shooting.
I think the difference is gang shootings typically take place in rough neighborhoods. When you enter a high crime area you're aware of an elevated risk. Innocent bystanders do get killed but it's probably a much lower percentage than the gang members. As horrible as it is, gangs are somewhat consenting to this level of violence by initiating it.
Terrorism and mass shootings are horrific because they typically take place in previously safe areas and claim almost exclusively innocent bystanders.
If you have children in school, they now practice "Code Red" drills where they lock the classroom and hide to simulate an active shooter.
Wether your pro or anti-gun no one wants the reality we have now where kids grow up with this kind of fear.
While the number of deaths from terrorism are far lower, the fear is probably far higher because kids grow up thinking/knowing it could happen anywhere.
I think for this reason people focus more on these mass shootings and how to prevent them.