>Simply put - guns reduce crime.
If it were so simple, every country would have doled out guns to every citizen. So far, only the Swiss have something of the kind.
Given the history, social mores and the general attitude of the people, maybe guns are making USA safer, because there already are so many guns in hands of criminals. Just like the SUVs are safer than regular cars because there are so many SUVs on the road.
As for the DC's experiment, it was doomed anyway: imagine if one city would forbid its citizens from locking their doors. What sort of people would this "open doors" policy attract?
IOW, isolated changes in policy will prove nothing, either way. Just as much as "locals won't have guns in DC, everybody else welcome to come here and shoot around" will of course make for very weird statistics, so is the Florida case not proving anything - the regular citizens weren't expected to register their guns for carrying because they had an intent to promote drive-by as a lifestyle, but for protection only. What matters is how many more guns did it bring out on the streets, how many of these guns got into hands of criminals, and possibly, how many criminals took those guns to other states with different laws?
BTW, I took the piece you quoted and blogged it to death, but from a different angle.