This is exactly what they did in California. First they registered the guns. Later, with the stroke of a pen, they made it illegal for certain "groups" of people to keep their legally purchased and registered guns. The police were dispatched to seize those guns. It will happen in Connecticut too.
California Seizes Guns as Owners Lose Right to Keep Arms
Wearing bulletproof vests and carrying 40-caliber Glock pistols, nine California Justice Department agents assembled outside a ranch-style house in a suburb east of Los Angeles. They were looking for a gun owner who’d recently spent two days in a mental hospital.
They knocked on the door and asked to come in. About 45 minutes later, they came away peacefully with three firearms.
California is the only state that tracks and disarms people with legally registered guns who have lost the right to own them, according to Attorney General Kamala Harris. Almost 20,000 gun owners in the state are prohibited from possessing firearms, including convicted felons, those under a domestic violence restraining order or deemed mentally unstable.
http://www.bloomberg.com/news/2013-0...bear-arms.html