Its a good idea to build a couple Patriot Missile Systems. Also, watch out for enemy Engineers who will attempt to take over your structures. Keep a couple Engineers around just in case so you can recapture your building in the event this happens to you. Now start producing GIs and have them garrison the buildings to the north to take care of paratroopers coming through that section to your base. Also take some GIs and garrison some of the building to the east.
Soviet paratroopers land there also.
The Soviets earlier in the mission have taken over the small Island of Niihau and set up a base there. If you don't stop them they will build a Nuclear Missile Silo and use it on your Naval Depot. You will need to move against this base as soon as you can. First, make 10 GIs and one Engineer and a transport unit. Send them north to the Tech Airport and capture it.