Your views are very idealistic.   That is not necessarily a bad thing.  But idealism bumps hard into reality every time.  Context IS important.  Life (and history) is not black or white.

Progress and democracy is messy.  Two steps forward; one step back.  It can't be any other way.  

I'm not sure how generously history is judged especially these days.  You really do need to understand the times to fully understand history.  It can't be judged correctly any other way.  

How would you stop the Syrian civil war?  Would you intervene against a sovereign governmen?.  Assad is a tyrant but that is a dangerous precedent.   Would you support the side of theocratic rebels waiting to install their own brand of tyranny?  Does the west cowboy into the middle east and make it all better (because that has always worked out well)?  Who decides?  You?  I hope you choose correctly.  And I hope history judges you fairly.