The Soviets still cover most of the globe. We must continue to fight them wherever they may be. A Soviet fleet has been discovered en route to Hawaii. Destroy this fleet and the Pacific will be ours. - Mission briefing
As the American military and civilian leadership return to Washington, DC from Canada, the Soviet Union was becoming increasingly desperate as they were losing their gains in the American homeland and were now facing attacks from the European Allies. In order to safeguard their presence in the Pacific, they decided to attack and secure the American naval base at Pearl Harbor, apparently trying to replicate the Japanese success of the Pacific War from the original WWII. This time American intelligence knew of this beforehand and set up outposts across the islands to defend against the invasion and dispatched their best commander to lead the defense.
The invasion did not take the Americans by surprise due to their intel beating the Soviets to the punch, but proved overwhelming to the Niihau outpost, which was leveled by Dreadnoughts and used as a staging point for the attack on Oahu, followed by a direct strike against the Pearl Harbor naval base. The loss of the outpost served to warn the Americans of the scope of the invasion and thus, they prepared for the assault and also began to build their navy to counter the Soviets, namely with their Aegis Cruisers to fight the Dreadnoughts' missiles and their Aircraft Carriers to pound the Soviets in retaliation.
Build a hovercraft, an MCV, and a couple engineers. load the MCV, engineers, and a rifle squad onto the hovercraft, the proceed north from Oahu until reaching Kauai (northern island). Once there, take the airport and have your rifle squad take up sandbag positions. (The Soviets for some reason only send a couple engineers at a time, no conscripts or tank even on hard mode). Deploy MCV and establish a backup base, starting with an ore refinery. This way, if by some miracle the Soviets succeed in destroying your primary base at Pearl Harbor, you will be able to continue preparing for a counterattack relatively undisturbed. A couple dreadnoughts may take pot shots at your barracks... that is what the Patriot Missiles are for.
Build several spies, disguise them as conscripts, load them onto hovercraft, and land them on north-eastern part of Niihau to the right of the tree. I wouldn't recommend using a helicopter, the Sea Scorpions will eat you for lunch. As the Nuke countdown approaches the last minute, move ONE spy to the south, while being wary for guard dogs. Move the spy into the Nuke Silo, restarting the countdown back to ten minutes.
Anticipate almost constant waves of Soviet land forces approaching from the north, east, and south areas of the map as well as routine naval attacks from the south. The first infantry paradrops will be notified of their arrival when the civilians around the drop zones scream and start running around in a panic for a short bit.
You can win this mission in approximately 2 minutes by sending the Destroyers to the west and destroy the Sentry Gun.
The Soviets in the northwest will construct a large base complete with an armed Missile Silo on the site of your ally's former base. Respond as quickly as possible and destroy the base with a large fleet of Destroyers and Aircraft Carriers but remember to keep your own base defended as well.
After every few minutes (roughly three to seven minutes), squads of Rhino Tanks and/or Conscripts with attack your base from the cliffs north of your location and from the nearby city to the east of the harbor. The north squads will usually target your Barracks before attacking any other part of your base. The east squad WILL try to destroy your starting Naval Yard before attacking the rest of your base.
There should be enough space on the island in the center of the bay to build at least three more Airforce Command Centers. Take advantage of this opportunity and build them with the maximum number of Harriers. You should use the Harriers to destroy key Soviet structures in the newly constructed Soviet base in the northwest area of the map. This will guarantee you a swift victory if you manage to destroy the Soviet Construction Yard.
You could also just build an Amphibious Transport and pack a few Engineers and capture the Soviet Construction Yard before the Soviets commence building their base, so to end the level quickly.
Tech Airport to the north. Soviets will attempt to capture it. Also an excellent spot for backup base in case Soviets get lucky in Oahu.
You defended Pearl Harbor with such ferocity that the Pacific is ours. - The mission debriefing when played faster than at par time
Pearl Harbor has been saved, but the Hawaiian islands have been devastated by the Soviet onslaught. - The mission debriefing when played slower than at par time
The Allies' destruction of the Soviet Navy meant that the Allies now controlled the Pacific Ocean. The Soviet Pacific Fleet would never play a major role in the theater for the rest of the war. Meanwhile Yuri's Psychic Corps struck St. Louis and implanted another Psychic Beacon at the Busch Stadium.
The success of the defense also secured a bold trust from the US Navy. In return the Navy will grant the commander permission to access their crown jewel program, the Navy SEAL, once Pearl Harbor is reorganized.
Despite the fact the Hitler was erased in the opening scene of first Red Alert to change history, the Arizona Memorial is still present in Pearl Harbor. It is possible that the Japanese still waged war against America without the formation of the Axis Powers. Thus, explaining why the monument still exists. The same case applies regarding the appearance of the Iwo Jima Memorial in the Soviet campaign's first mission, Operation: Red Dawn. However it's also plausible that the two war memorials are presented just because following the game design that features well-known touristy sights in United States such as Statue of Liberty, Jefferson Memorial and White House, etc.
Even though the Pearl Harbor seen in-game is only a representation, it is still considerably down-scaled for even the standards of the game. The actual harbor is large enough to hold over forty ships but, the in-game version can only hold roughly twenty or thirty without any moving space left available.
In the game, the Allied base is located on the west side of the harbor. However, in terms of actual history, the base should have been located on the north and southeast sides of the harbor. This change was probably made for gameplay reasons.
In Mental Omega 3.0, this mission is reverse remade with the player controlling the Soviets, and additional land masses with Allied bases in the northeast and southwest corners of the map.