Act of war and it's expansion High Treason, are what the C&C Generals pretended to be. Best modern warfare RTS.
For me games are an imitation of reality. A chance to be someone you'll probably never be. The only RTS to date to really adress this issue is Act of War. On the top it didn't seem any different than C&C, but you'll see the difference in the first battle. When a mortar shell hits a group of enemy soldiers they fly to the ground, instead of losing 50% of health and still firing away. When a soldier is badly wounded he has to be evacuated to avoid capture, and he can't do anything other than tell you "Goddamn it hurts!".
Now how many movies of evacuating wounded and saving POWs in Vietnam have you seen? Who has ever implemented this into a RTS?
The almost perfect unit balance, the combination of authentic military hardware used today with futuritic designes, the attention to detail, all add to the atmosphere of A Real War. A war that might happen even today.
In Act of war not only numbers and technology are important, but also tactics. And that's what matters in the real world.
My only complaint is the lack of an Naval AI in scirmish . The Navy adds so much more depth to the game. But I guess you can't have it all.