Fire Base - The Firebase is basically a fixed long-range cannon, which can be garrisoned by four infantry for added security. It does not, however, offer any protection to the infantry garrisoned, and they can be harmed by toxin, radiations and snipers.
Detention Center - The DC has been removed from the game entirely. Its intelligence capabilities now are available at the Strategy Center.
Sentry Drone - The odd little Sentry Drone is intelligence in a can. Immune to anthrax and radiation, this quick robot can detect stealthed units, and becomes invisible itself when totally still. The Sentry Drone is a rare sight online because it adds virtually nothing in combat. It is also the only existing vehicle that cannot run infantry over. With a $1000 upgrade, all Sentry Drones are given 20mm guns, which allow them to act appropriately when hero-hunting.
Avenger - The expensive Avenger serves three purposes. Firstly, it rapidly neutralizes incoming enemy missiles. Secondly, it increases the rate-of-fire of all units attacking a certain target. Finally, it brings down enemy aircraft in a deadly lightshow. It can perform all three of these tasks at once, and is therefore very useful in a large firefight.
Microwave Tank - The Microwave beam emitted by this unit kills the infantry garrisoned in civilian buildings and temporarily disables all player-built structures. The infantry units within disabled structures are, in turn, disabled. The Microwave Tank will automatically damage any enemy infantry in the area. It can also disable defensive structures.
Ambulance - The Ambulance not only heals nearby infantry, but now repairs nearby vehicles. (With the exception of aircraft.)
Stealth Fighter - The Stealth Fighter can now be upgraded with Bunker Busters, which kill the infantry within ANY structure, even dozer-built ones. If used on a Tunnel Network, the Bunker Buster kills all infantry inside and forces all vehicles to evacuate.
Countermeasures - Available at the Air Field, this $1000 upgrade allows all USA aircraft except Chinooks and the new Combat Chinook to defend themselves from missile-based attacks with periodic flare-drops, including the planes called in by support powers, improving their survivability during bombing runs.
Hellfire Missile Drone - All USA vehicles can now be equipped with this drone, which fires hellfire missile at the enemy. The missile does more damage to vehicles, but has a slow reload time. It cannot, of course, be used in conjunction with the other two drones. Each drone costs 500.
Chemical Suit - Equipping all USA infantry with chemical suits, which grants them high resistivity to toxin and radiations. This can be proven handy against the GLA. Available at the Strategy Center.
Supply Lines - Increases the productivity of Chinooks to boost your economy. Available at the Strategy Center.
Bunker Buster - Upgraded at the Air Field, Bunker Buster allows Stealth Fighters to kill garrisoned units within the building. See the column at Stealth Fighter for more information.
MOAB - Available at the Strategy Center, provided the Fuel Bomb Generals Power is selected. This upgrades Fuel Bomb to MOAB Bomb, which greatly increases its damage, making it almost as strong as superweapons.
Leaflet Drop - Calls in a transport plane, dropping leaflets at targeted area, renders affected enemy units temporarily immobile.
Spectre Gunship - Deploys a monstrous Gunship to hover over targeted area and reduce anything in sight to rubbles with its powerful machine gun and howitzer cannon. The player can manually control the gunship while it's hovering. The gunship can only attack targets within range and can be shot down under heavy fire. When switching targets the machine gun will continue to fire from the original target to the new target area, then after 3 seconds will commence to fire the cannon.