If I'm not mistaken, the cosntitution says you have a right to keep and bear arms in your home. If you leave your home by horse or buggy, your firearm must be unloaded in plain view or be in a locked strongbox.
They just reafirmed this in D.C. Scotus shot down a ban on gun ownership in the home, but left no provisions for RKBA outside the home.
Do I really need a sarcasm tag?