I highly doubt it.
Without the promise of an Afghanistan withdrawal I doubt trump would have been elected. Without the drastic shakeup that was the transition from Obama '12 to Trump '16, and the sheer parade of divisive issues that have followed, I highly doubt the situation would be as it is right now.
Would it fix everything? Of course not. But if I wanted to fix everything wrong in America we'd have to go back to the Reconstruction, if not before. I'd just prefer it didn't look like we were staring down the barrel at a powder keg.