What you are proposing is a separate, Black nation. At the moment, most Blacks do not want this. If they ever do, patriots should support their right to have one -- as they should for any national grouping. The specifics of it would be very messy but that's how humans make their history.
In the meantime, we have to live together. All patriots, of whatever color, need to support strong measures against all criminals, of whatever color, including against petty crimes, which is how serious criminals get their start.
We need to support School Choice, which will separate the disruptive, incorrigible ones from the salvagable ones.
The coming collapse of America will root out old political loyalties. A lot of people who have voted Democrat all their lives, will see the practical, bloody results of the Democrats' pro-criminal policies. We can wina lot of these people over. But not if we say, "Only whites allowed." That's a criminally suicidal policy.