It's true, I've never seen anyone wear a shirt that had anything about the US military on it! Certainly the US military doesn't have a store to make money on merch!
This would-be shooter's life story is interesting. CalTech but then couldn't hack it in the real world like...at all.
I'm going to guess his life story is the sad reality of DEI: black males are the most underrepresented demographic category for colleges, so black males can get in with the lowest test scores and grades, even lower than black females. So a kid whose performance in no way genuinely qualifies him for an elite school gets in anyway, gets DEI C's until graduation and a couple of choice internships all based on the color of his skin....but has some kind of genuine personality issue or something that makes it so even the DEI hives of California won't give him a job. It looks like as long as his paper applications were doing most of the work, he did fine, but that as soon as he spoke to corporate interviewers they immediately knew it wasn't going to work out.