I guess the Army and Marine Corps are inherently evil too, which is why we'd never want the police to resemble them in any way whatsoever.
You don't want the police to resemble an army because both, idealy, have very different goals. Military is supposed to have a maximal impact on the enemy with as few friendly casualtys as possible. Police is supposed to uphold the law, the term of "enemy" should not exist for a police officer. In the end police is there to protect citizens.
If there is a situation that regular police forces can't handle there are always special forces like SWAT in the US or the GSG9 in germany. Regular police officers don't need access to military equipment because for what they are supposed to do that stuff is simply not needed. Especially if they are clearly not properly trained to use that equipment (see Ferguson).