What kind of civilization keeps enough armament and nuclear capacity to destroy the world ten times over?
Well, to nitpick, none. All of the nukes in the world won't destroy the
industrialized world once over, nevermind ten or more. It'd cripple the infrastructure, kill hundreds of millions and ruin the global economy for many decades, but it's not like these "handful of white men" have access to the fucking Death Star

That's a huge contradiction. And it's all in the hands of a few white men too. Literally.
If a build up to gigaton-ranged arsenals happened overnight, yeah, sure. But that didn't happen overnight.
Further, the nuclear deterrent probably
prevented a great deal of conflict. The Soviets and U.S. were on the verge of war more than once, but knowing that war might lead to essential MAD, cooler heads prevailed.
That's not to suggest that building a huge nuclear arsenal is inherently "peaceful," but then,
those white men never used the nukes, did they? 
Comparing their restraint to a bunch of racist assholes using some guy's death as an excuse to go burn down their own neighborhood isn't at all comparable.
One more thing. In your OP, you talked about how white folk are violent, too. Err ... so? Tu Quoque. Humans are violent -- no doubt about it. That doesn't change the fact that a particular culture's more prone to act like jerks when they're mad at the Po-Po. But I do think that's more a function of environment than ethnicity, strictly speaking.