I'm sure someone will come along to better explain it, but basically to win the war, your country has to own a certain percentage of the other two countries' bases and a certain percentage of your own.  These bases can be captured with 10 troops after certain circumstances for airfields, vehicle bases, and ports.  A lot has changed over the last few years, and I am not really up to date with it.  Hopefully someone a little more well-informed (like Lusche), will answer these questions for you. 
#S#
Josh