Legislation which - if history is any indicator - will do nothing to prevent tragedies like this, and will actually make our society more susceptible to this sort of thing, as fewer people have the means to defend themselves

I'm not meaning to preach, but what historical indicators are you using to base this on? What exactly about this makes you think that our current system ended this any better? What makes you think it would have been 33 instead of 32 if it had been harder for the shooter to get a gun? As for defending themselves, was there a mad rush of gun owners running into the building to plow this guy down that I'm unaware of?