I'm pretty liberal (no shit) but I also like facts. So a few points from things I've read in this thread:
-No it is not the 18th school shooting this year. While unacceptable by any measure, the number is far less than that. That figure comes from a gun control group with questionable methodology. Their methods basically consisted of "Did a gun go off on school premises in any context?" If the answer is yes, that was included as a school shooting. So included in that eighteen number was a man who committed suicide in the parking lot of an abandoned school, two kids who shot at a school building at night with no students present, a number of accidental discharges (one from a school cop's gun), and a number of incidents where no one else was hurt (discounting the suicide).
The Florida shooting might be the 2nd one this year, by usual mass shooting parlance. I say "might" because the CA shooting a few weeks ago that hurt a few children was deemed an accident. Does it raise questions like "Why bring a gun to school at all?" Of course, it does but the arrested child did not come to school intent on murder.
Focusing on AR-15s as the mass shooter's weapon of choice misses the point. Is it a civilian, semiauto version of a MILITARY weapon? Absolutely. If anything will ever be done about guns, a more robust conversation is required. The VA Tech shooter killed roughly twice as many as yesterday's attack with two handguns and no "assault rifle." We can have as bad or worse an incident as yesterday even if the Assault Weapons Ban were reinstated. There are a bunch of little steps that can move the country forward but one party would rather take money and influence from the biggest lobbying group than protect children and everyone else. Our Congress is so craven that we can't even write legislation to outlaw a device that effectively circumvents the ban on automatic weapons-- which is how the worst shooting ever happened (October 2017). I'm not asking for banning guns because it is impractical in a country where 300 million guns are already in circulation. But the status quo right now is erring on the 2nd Amendment rights of a citizen rather than abrogating that right if he or she might not have the mental state or temperament to own a gun.
Also, Obama made a few minimal steps but was mostly blocked by a Republican Congress. Of course, when you stake the wingnut position that Democrats are coming for your guns--which has never been proposed--it's hard to have reasoned debate. Gun prices and units sold soared during Obama's tenure because he was "coming to take the guns." That never happened so they moved onto Hillary as the next bogeywoman (?). Someone told me in 2016 that if Hillary won, guns would be outlawed and the police would go door-to-door to retrieve all the guns in America (yeah, remember that 300 million number from earlier? Yeah, we have a lot of stupid people in this country. Incidentally, this guy watches a lot of Fox News). Now gun demand has gone down with Trump in office.