The move to a militarised state isn't just about the hardware they have inherited... but with it came a mindset of dehumanising your enemy
it's certainly true that military equipment will lead to military outlooks and military responses
but also - the police have always treated black people with dehumanizing, often lethal contempt. they've always disregarded human rights. they've never tolerated criticism. in my city the cops had a fucking illegal secret detention facility until 2015! this is what they do. the hardware makes it more likely they'll kill more people.
even worse I think is the rise of more or less law enforcement-sanctioned paramilitaries, their blurring with law enforcement, Trump's tacit or open approval. that's how death squads happen - paramilitaries mixed with out of uniform cops and military. plausible deniability.
I'm not as pessimistic as droid but he's not wrong that you can easily see the possibility.