The police defend the people within the U.S and fight the good fight, If they need military-Grade weaponry to protect citizens, have at it, our safety should be held at high standards to ensure our protection.
So if police sometime in the future pick sides and your side is not the one they pick. And they start rounding you up and you resist and they use those military grade weapons on you. Is that OK ? Don't say it couldn't happen. Look at the country now...