Disbanding must be done by the state, but while waiting for that to happen, local communities can internally agree to recognize NFAC-style groups instead of police as authoritative, and discourage police from entering their territory using firepower, thus creating a no-go zone. This can hopefully serve as a temporary fix while waiting for action from above.
https://abc7chicago.com/fbi-chicago-warns-that-gang-cabal-may-be-targeting-police-officers-/6397730/street gangs "have formed a pact to 'shoot on-sight any cop that has a weapon drawn on any subject in public'."
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The "situational information report" from FBI officials in Chicago dated August 26, 2020, states "members of these gang factions have been actively searching for, and filming, police officers in performance of their official duties. The purpose of which is to catch on film an officer drawing his/her weapon on any subject and the subsequent 'shoot on-sight' of said officer, in order to garner national media attention."
(I of course also think ICE and CBP should be included in the above as even higher priorities, and they should not even be required to draw their weapons.)
And while you talk about starting from scratch, doing so does not prevent corresponding re-infiltration from scratch by racists (though it may take a while). So then we look for measures to filter out racists at the selection stage, but then we remember that clever racists can pretend to be anti-racists in order to get past the filters. Thus the only true solution is to eliminate racist bloodlines via state control over reproduction. Which is of course what we have been saying from the beginning.