Individually, they're dumb, out of shape, and, if you've been paying much attention, pretty cowardly. So yes, a single cop is fucking joke. But as a group they're better-armed than many militaries, are legally protected from the VAST majority of their own crimes, and have an insane culture of solidarity not only internally, but with the moneyed class.
You fuck with that loser once and you're inviting a team of violent idiots and a judge to legally fuck with you the rest of your life. You actively defend yourself from that team of violent idiots and a judge in turn, and I am not exaggerating when I say you're inviting a militarized response. There's a reason that so many of our cops can get away with being so mean, dumb, and weak.
Realistically, our local and federal law enforcement has always been like this. See: Blair Mountain, Black Wall Street, the Jim Crow South, the post-Jim Crow South, any of the L.A. Riots, Ruby Ridge, the entire history of the Texas Rangers, COINTELPRO, Black Lives Matter, or the life and times of J Edgar Hoover, just off the top of my head.
The only difference right now is that we've let it get so out of control that now the average white American are getting caught in the collateral of what is otherwise standard operations. So now it gets treated as unique. But it's the same shit as always, just bigger.