Hearts of Iron 2 is a must for WW2 strategists and anyone who asks "what if?"
Gameplay is what you're looking for when you pick up Hearts of Iron 2. The game features incredibly deep and involved combat. Defending your country from advantageous terrain, avoiding attacking across rivers or marching through jungle, encircling and capturing enemy divisions, gaining air superiority, and choosing the time of day at which to launch an operation all factor into the combat. The game can be as easy or as hard as you want, depending on what country you play. Playing as the United States allows you to sit back and build up your industry, whereas playing a country like Poland is very challenging, as you risk being assaulted in 2 different directions by 2 different superpowers.
I highly reccomend Hearts of Iron 2 to true strategy fans everywhere, because it's so addicting and fun and yet it is often overlooked in favor of lame, flashy games. it is worth every penny.