We could turn New York and Los Angeles into giant prisons...

https://en.wikipedia.org/wiki/Escape_from_New_York

http://en.wikipedia.org/wiki/Escape_from_L.A.

BTW, this is why the US citizen does not worry about the government attempting to put us all in prison.

http://en.wikipedia.org/wiki/Number_of_guns_per_capita_by_country

At 94.3 guns per 100 people, it would not be an easy thing to do.  Of course, the number of gun owners per 100 people is a bit lower but that just means it is harder to find the guy with the gun in the crowd with out pissing off the rest of the folks.