Oh man! Here I go again! Once more, the universal game for everything, "Brothers in Arms". Absolutely demands squad tactics and presents them well. Very tactical (unless on "easy" or "normal") and with a reasonable difficulty curve. You are in charge of a squad consisting of, well, you and then a fire team and an assault team (they usually consist or 3 or 4 men). You can tell them what to do and where to go. Basic tactics include using the fire team to suppress the enemy and using the assault team to get a good flank on them while they're busy. The game requires thinking situations through, assessing options, and making those cliche "tough decisions". Out now are "The Road to Hill 30" for original xbox and maybe ps2, "Earned in Blood" for xbox, ps2, and PC, and coming in August, "Hell's Highway" for xbox 360 and PC.
If you're into squad-based games, you have probably already heard of these and I'm just spouting needless, annoying information. If you haven't heard of them I would strongly suggest the purchase of these gems. They do not disappoint. I have the two that are currently out and I'd say they are the best WWII shooters ever made. But what's my opinion to you? You'll have to see for your self.