They realize that even with a national furor over this incident, the drastic step of full ban or national ID would be impossible. So, they'll opt for the incrementalism - ban on extended mags, then mags that protrude, mags more than 5 cartridges, then down to 3, etc.... If he recently purchased the weapon, you may see a simultaneous call for extended waiting periods, etc.......It is their way.
That IS incremental, from my perspective.
What they’d really like to do is create a police state and try to collect all our guns.
I expect a big push to do something like create uniform gun laws in all 50 states; special training for all gun owners, etc., etc.