The thing is, most Chicagoans do not make use of the Great Lake we live next to.

The vast majority of crimes are due to repeat offenders and "known gang members". All the government needs to do is load them all onto an old cargo ship, tow it out to the middle of Lake Michigan, and then sink it. Crime plummets, scumbags that are thinking of misbehaving are more leary of the consequences, and the majority of us live in a more civilized land. Problem solved.