The US Supreme Court has settled an issue as old as the Bill of Rights: individuals must be allowed to own guns. But Justice Antonin Scalia, writing for the majority, also said, "Since this case represents this court's first in-depth examination of the Second Amendment, one should not expect it to clarify the entire field." Both sides have predicted a flood of lawsuits to seek "clarification," and sure enough, they're already being filed. If they can't ban guns, what kinds of regulations can governments impose? We ask about background checks, registration, assault weapons, trigger locks and carrying concealed weapons. What about gun crime and public safety? How long will it take to sort it all out, city by city and state by state?