You never really know exactly what will happen, even when you make the right choice. Decisions have outcome probabilities, and those outcomes have side effects, which are also governed by probabilities. You have a good inkling what the consequences of a decision are likely to be, but you never know with absolute certainty what the ripple effect is going to look like.
Vance Strickland has a write-up over at Grogheads that shows how some of the "non-military" aspects of the game work. Here's the link:
http://grogheads.com/?p=9448
I'd also suggest taking a look at the developer blogs in the Decisive Campaigns: Barbarossa section of the Matrix site.
History is a bad joke played by the living on the dead.