Watch Trump and his cronies (Session) using this as an excuse to batter the FBI for failure to act.
I'm not being funny but if the FBI had to react to everyone displaying the shooters behavior: desire to kill people, erratic behavior and bizarre social media posts. They'd have to incarcerate half the US population!
Oh and BTW the NRA were doing tweets for Valentines Day telling lovers they should buy each other a gun for a gift! That was swiftly deleted after this latest massacre.
For the record the UK's last ever mass shooting at a school was the Dunblane Massacre in 1996,. Following that hand gun private ownership was banned. There have been no more mass shootings at a school since.