Serious question: Why are so many people "going postal" in the US as of recently? "

I see two big things.

1. Everyone is frustrated with the government, and a whole lot of people feel like voting doesn’t do any good. Most people are simply not aware of any constructive ways to effect change.

2. To those frustrated people who feel like they can’t solve their problems in a civilized manner, assault weapons tend to be easily available.

1. A permission structure that mimics the fat slob who is cosplaying being president with his credo: "I hate my opponents. I don't wish them well."

2. An economy that is being presented as "hot," but is shedding jobs with limited opportunities, and growing dissatisfaction with day-to-day living.

3. An authoritarian rigor that is encouraging the classic human revolt against authority figures.

4. A craving for social media attention.

5. Burnout from all the above.

The answer is bigger than any one thing, but a good deal has to do with Trump's incessant spreading of lies and hate. His unpatriotic actions are also a big concern.

Mental illness has nothing to do with it. The overarching problem is right in front of everyone: how the media covers mass shootings. But people aren't smart enough to recognize it and instead waste time debating non-solutions like stricter gun control laws or better mental health care. Because of that, nothing is going to change. American society simply isn't astute.

Too much THC in the weed.

Someone stirring up the ant colonies just to see them fight maybe?
You either can react and engage in the politics or stay distant and observe.

American problem! ✋
Hint-

Because the left is losing their control...when that happens, the violence increases.

That’s nothing new. The phrase “going postal” dates back 40 years.

Socialist mindsets.

If you keep listening to the left tell you people who disagree with you are pure evil, it exonerates you from murder in your mind.