There is no easy fix for the problem, because any solution requires both the protesters and the police to come to the middle ground.
The police and federal agents need to show respect for the peaceful protests during the day and the protesters need to respect a reasonable curfew so police can do their work stopping rioters and arsonists at night.
Showing up in militarized uniforms and teargassing/shooting peaceful protestors doesn't bring us closer to that middle ground. Neither does destruction of property and defending rioters/arsonists.
That was the hard fix. I don't believe the feds will be able to solve it this time by doing what they did in LA in 1992.
And if we simply restore the status quo using a show of force then these riots will happen again and again.