So you're saying that even with uber-militarized police nothing can be done about gangs?
Of course something can be done. But it's politically incorrect to do so. The most violent gangs are thick with illegal aliens from Central America. The leftier side of US politics really wants to be able to take legal Latino votes for granted. So they angle for policies that do everything possible to avoid ruffling feathers in that area
To deal with gangs like that, you have to actually arrest people and then once they're in prison, actually keep them there. We don't do nearly enough of that - the revolving door has those guys right back in action after short terms, and their habits of recruiting minors for a lot of their dirty work means little or no jail time for a big part of their operations. If they're deported, they just show right back up because we have a completely porous, unenforced border. That's only true because the federal government isn't bothering to do one of its main missions (controlling the border), and that is a 100% political problem. The existence and violent toxicity of powerful, organized, nation-wide gangs (like MS13) in the US is then left to local law enforcement to deal with.
So yes, when they move to deal with a place known to be protected by a bunch of MS13 soldiers, you better believe they want to show up with heavy equipment. Would you bring a nightstick to arrest a bunch of MS13 enforcers who consider killing police officers, cartel-style, to be a sport and a point of pride?
But none of that has to happen. Controlling the border and not tolerating tens of millions of illegals in a shadowy cash economy rife with internal, organized crime - it's a matter of political will. But because there are politicians who are too timid to talk plainly about it, and who would rather play identity politics in a craven hunt for votes, we have a system that perpetuates rather than addresses the problem. And the local cops get to risk their necks as a result. If I were in that line of work, yeah, I'd want an armored car when serving warrants, too.