These walkthroughs are designed to give you sufficient knowledge of each mission to find it easier, but not lead you by the hand all the way through...it's much more fun when you do some of it yourself.
Wow, I was surprised with how easy this mission was. There's a minor assault at the beginning with a few units of infantry, this is a great opportunity to test out your new drones, which EA was nice enough to give you three of to begin with, along with the nose-mounted gun upgrade (formally "Sentry Gun Upgrade"). But, this is just a quick little intro to the USA, more or less. You can push your way north/northwest very easily, encountering minor resistance until you come to the train station. There's a small complex to the east on this path that leads to an abandoned Chinese facility. There are a couple Battlemasters, an Overlord, and a Flame Tank there for you. I just commandeered the Overlord, and slapped a propaganda tower on it to heal all of my assault party. With my infantry-loaded humvees and a handful of Paladins (all with Hellfire drones, very nice to have), along with my now complimented force of 6 Drones, kicked the crap out of the GLA for the rest of the mission, which is incredibly self explanitory.
You're given so much firepower on this mission, it's not even funny. You get some moderately powerful artillery strikes, what makes it crazy is you can do 5 at any given time and they recharge very quickly. You also have about 20 (estimation) raptors at your disposal. Just start using those a whole lot...when it comes time to destroy the GLA, after the supply trucks are taken care of (don't worry, you can let them go undefended and they'll be fine). Have your raptors guard the area over the GLA base, so they constantly make runs, laying waste to anything stationary. Use artillery and those and you'll have this mission won very quickly.
Stealth time! It's pretty cool actually, at least for a little while. You have Colonel Burton given to you once again, this time he's Heroic though, sweeeeeeeet...Well, he can do most everything for you. Take him and garrison him in a building next to GLA garrisoned buildings in the town to the northeast. He'll take them out without problem, even two at a time. Move him north, outside of the oil derrick base of the GLA. Move up your snipers just north of the town Burton cleared out, and have your Drones not far behind just in case. Those snipers will pick off lots of infantry moving through that area. Take out those oil derricks first off, cut the funding. Have your drones move up and help Burton take out tunnel networks. Once this area is cleared, you have a 3 Paladins and a Microwave Tank waiting for you, and the troops to take them over. Then move westward to the other POW camp and take that out, and get a few infantry. Once that's done, then just use your armor (paladins, microwave tanks, drones) to move northward and escort Burton to the mountain. Not too tough, but tougher than 1 & 2...put together.
Finally, a little bit of a challenge! But a really fun one. Ok, call me a newb for loving to play defensively for a bit, but you go on the defensive here right away. You've got a bridge immediately to your west. They may not use it much right away, but get two firebases there ASAP. Build your command center at the end of the runway, a ways out. Then build a firebase just beyond that. One last firebase by the eastern oil derricks. In each one put one sniper and 3 Missile Defenders. Unstoppable. I took those humvees, put 3 Missile Defenders in each, along with 2 rangers. Upgrade to TOW missiles and Combat Drones, and you're good to go. They'll really help alot on the defensive. Just be careful not to let any get destroyed, they're pretty valuable at that point. Once you've gotten enough promotions, A10 strike the radio station in the north. You'll need to strike it twice, or once and send up your humvees. Then move westward to the oil derricks over the bridge. Paradrop in as many men as possible, and bring along a Dozer to eliminate booby traps. Have one man per derrick, capture as many as possible as fast as possible. Burton for cover here is great, they never send any anti-infantry. I also had 5 Sentry Drones with the nose-mounted guns there for cover and detection of booby traps. As soon as you have these, push your infantry north and capture the three artillery platforms to keep the GLA confined to their area. Now they're screwed, no money and no way out. Use those humvees to obliterate their base. You can also call up all those tanks you've got for reinforcements now, put up some hellfire drones on them, and wreak havoc. Either way, there's only two things you need to look out for in that base. The first is SCUD launchers, they'll rip Humvees and Sentry Drones apart. Secondly is the tunnel network - when I play, it had quite the army inside of it. Keep that in mind during your assault and you should have a clean victory.
Well, this one isn't too difficult either. First off, build 3 patriots just north of your starting location. Most if not all attacks on your base will come from there. Behind that, strategy center with a cannon, and a firebase with 4 Missile Defenders. There. Now that nothing can touch your base, let's move on. I built an air field, upgraded everything and built 4 raptors, and 8 commanches. I also had a small ground force of paladins, with an assortment of all 3 drones. There are quite a few demo traps around, so watch out for them. Build up experience with strategic air strikes with your raptors, and when applicable send in Commanches and the Paladins to clear stuff out. You'll find your objectives, the 4 missile silos, in the northeast corner and north-central area of the map. Use your superweapons and abilities, you finally have all of them, enjoy them. The MoAB rules, and the Spectre isn't bad either. Total air superiority, they don't invest much in anti-air. Use paradrops or chinooks to take care of capturing the missile silos, and you're done. Congratulations, the US campaign is over.