That already happened, the arrests are happening, and social media, normies and of course, the professional liars of the media are all squarely on the side of the migrants, up to and including the family of the guy who got attacked. Watch how they will force him to "send a message against hate" right away when he is out of coma.
People are vastly more optimistic about the revolution breaking out than its warranted. They simply don't realize where the hard limits, the hard rules, the real rules that might be unstated but mercilessly get enforced are. The establishment jailing people for years over twitter posts and letting thousands of rapists run is not going to get voted out of power and people are still too comfortable to revolt