The sad thing is in a discussion about handling the wrong kinds of attacks, everyone is still focusing on the wrong kinds of attacks.
The face of him violence in America is not splashy terrorist attacks like this one.
It’s one of two people getting shot with a pistol. Robbery gone wrong, bad drug deal, whatever.
That happens often enough every day that it dwarfs these big, ugly events. It makes these events statistically unimportant. Less than 10% of the murders in the US are committed with long arms, and assault rifles are a small part of that.
See the FBI’s UCR website (https://ucr.fbi.gov/ucr) for a LOT of information on crimes in the US. Table 12 for 2016 has a lot of interesting data on what kinds of weapons were used where for murders. https://ucr.fbi.gov/crime-in-the-u.s/2016/crime-in-the-u.s.-2016/tables/table-12.
Actually looking at the data has convinced me that any focus on long arm regulation is just a grandstanding move that will accomplish nothing. Gun Control Is Security Theater.