To quote Feynman: explaining how something happens makes the why irrelevant.

Feynman did not deal with humans. Knowing that Lincoln was killed with a bullet does not lessen the value of why he was killed.

The how can often be determined. The why is often conjecture after the fact. History is written by the victors.

Well, we had years of more claims than evidence. Somebody had to do the hard labor for sake of future historians.

I hope someday democracy has recovered to the point where we can centrally plan, and then we can experimentally historical theorys.

You can't explain why until you have a really good description of the what.