In order to provide citizens a constant reminder of the occurrences of mass murder by gunfire in this nation, the national ensign of the U.S. should be kept on display at half-staff as long as it has been 30 days or less since such an atrocity.
The citizenry shall be kept so advised of these crimes. The legislatures, both national and of the individual states, and their executives, shall be thereby publicly shamed for their implication by inaction until such time as this serial tragedy has been addressed to the BEST oh their abilities.
Suggested for a 1st step: Severely limit to size of any individual's personal arsenal of firearms. Perhaps a total of no more than 5 weapons? And no more than 500 total rounds of ammo?