After effects is out of the question. It doesn't do the same things as Vegas and Premiere so initially you have two choices. Premiere or Vegas?
This depends only from you. Which one you know better, both are very good. I would suggest you Premiere because it can be combined with After Effects easier (in case you use After effects after all).
That's a lot of learning just to do YouTube videos. By the way, After Effects should not be included in that list. It's a compositor rather than a traditional editor (and a freakier learning curve).
If you are up to the months of learning it, I'd go with Premiere (since I use it). It's popular among users so there's a lot of help out there for it. After you tackle it, that's when you go for After Effects for post production effects processing and buying additional plug-ins.
Be warned that not only is the editor expensive but the plug-ins and learning materials are as well. If you want to get up to speed quicker, you may want to go with something a couple of notches down like Premiere Elements or one of the Vegas versions. Maybe Pinnacle Studio.
If you need to do multiple tracks and masking for limited compositing, you will need Premiere Pro or Vegas. The best part? If you go this route, you'll be wayyy ahead of most people cranking out Movie Maker videos on YouTube in your knowledge of editing.
You just have to be willing to put in the time.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.