"The last thing I'd do is try to take on an active-shooter (especially one armed with a rifle) with a handgun and only engage in gunplay as a last resort."
I would have thought encountering an active shooter constitutes a last resort situation.
How many people does the active shooter have to shoot before you venture to do something about it or doesn't it matter as long as he isn't shooting at you or your family?
Good intentions will always be pleaded for any assumption of power. The Constitution was made to guard the people against the dangers of good intentions. There are men in all ages who mean to govern will, but they mean to govern. They promise to be good masters, but they mean to be masters.