And y'know what they weren't wrong, right up until WW2 more or less shattered the empire by overstressing and over extending it. There was no such pressure on the South without men like John Brown, reminder he wasn't the only abolitionist raider just the one with the biggest militia and who earned the most glory.

But we can go round and round on this one indefinitely, I generally see pacifism unbacked by the threat of violence to be worthless and even with that backing I consider it contextual at best. The pacifism of King and Ghandi were nothing without the violence of Malcolm X and the Indian revolutionaries.