Because the “Democrats” are actually Marxists. Every time this type of effort has any success, it helps with Antifa’s (actually Marxist) recruitment, which is the result the politicians want. If a different result is desired, then Antifa should never be allowed to win. There should be no delay in the response. The perpetrators should be treated as criminals and taken off the streets.
Remember the attempt to recall the Seattle mayor? She was being recalled because tear gas was “indiscriminately” used against the demonstrators/rioters, not because little was done to protect private property. If an attempt was made to recall the mayor for that reason, Antifa would have targeted the property of those leading that recall without having to be concerned about anyone resisting them. This is the ideal situation for the Marxist to grow their power.
This problem has been brewing in the Seattle area for decades, with the incessant promotion of victimization and hatred of those who have achieved success. Things will get much worse before there is any chance of it improving.
Very soon if 2020 election fraud is not overturned these people are going to hit a wall, And they will have a movement, but not the one they expect.