> without the stick of Malcolm X, King would have been cast aside

This is very much a supposition. A credible one. But not settled history.

> Nonviolence wasn't simply some magic bullet that was magically better than force, it was a political tool that seemed nicer compared to the alternative of force

Fair enough. And perhaps showing a group of people movitated enough to credibly threaten violence demonstrates their potency as a political bloc. But the value is in showing organisation. Not in the violence per se.

Levying violence as a political tool a dangerous game. If that rhetoric turned to action, the civil-rights movement would have been destroyed. By popular command.