The thing that hasn't come up yet, is escalation, cops get better guns, so the crims follow suit.
The biggest reason why I am against this move, is that I don't trust cops, whether on or off duty. This is not against anyone in particular, if you are a cop reading this, good for you. But when you consider that if you wish to join one of the armed forces, you mast pass a psychological evaluation. Cops do not, and these are the people that are supposed to be protecting and serving the people. Though in this day and age they really only protect and serve politicians.
Don't get me wrong, I have met some fine police officers in my time, but I have also met quite a few that should never have been allowed on the force. Those are the ones I am worried about, one day when the bubble bursts, or the stress gets too much, something bad is gonna happen. It usually does.
Don't worry, even I think I am paranoid.