There will be very little reaction. The MSM will draw some sort of moral equivalency. There will be calls for peace and reconciliation. The meme will be that the shooter had legitimate concerns, but he should not have tried to take justice into his own hands. There will also calls that reform of the police is now more urgent than ever.
There will be an attempt by the political and media elites to downplay what happened. They will try to hide the details as much as possible.