Of all the challenges on hard difficulty, by far this mission is the easiest. As with every fight against the Air Force General, the key to winning is anti-air defenses. As an infantry general, your Red Guard replacement unit, the Mini-gunner, is a wonderful anti-air infantry. Build lots of mini-gunners and Gattling cannons (do not bother with tank hunters.) You can also build a few bunkers and stick your mini-gunners inside. The benefit of a bunker is that they will absorb some punishment, you can repair them, and if they are destroyed your men are usually alive.
Once you have a stable defensive perimeter of anti air up around your base, start teching up. The first thing you should upgrade is your gattling damage from the war factory. Then build your propaganda center, internet center and Nuke Silo.
Build a Black Lotus, one or two Dragon tanks (don't forget the upgrade) and three Assault Troop Transports. Take all of those units and move towards the center of town. Use Black Lotus to scout ahead, use the Dragon tank to take out garrisoned buildings, and use the Troop Transports to defend the Dragon tanks from land and air attacks (though the only land attacks are a few extra infantry from the center of town.) If you are quick enough you will easily take out his supply choppers before he empties the center supply dock. This will strangle his economy. He will of course retaliate (by air) but your troop crawlers should be up to the task of defense; if one or two get killed, have the troops garrison a nearby building.
You should now be softening up his defenses with your Nuclear Missile and Artillery barrage General Power. Build a few Inferno Cannons and/or Nuke Cannons along with a large force of troop crawlers. Use the cannons to take out his patriot missiles than move the troop crawlers in for the kill.