Actually, I think it's a brilliant idea that would serve a dual purpose.
First, as stated above, if they want to fight, let them fight. They can not only fire all the semi-automatic weapons they want, but they will get ISSUED said weapons from the Government to do it with. I would think it would be a gangsters dream. It also gets them off the streets and makes things safer for us.
Second, use them as "expendable front line grunts" by sending them first into battle, which as we all know, are usually the first ones to come back in burlap bags.
That way the real soldiers have improved odds of survival, and once again, we've disposed of the gang bangers.