With the battleships at the bottom of Pearl Harbor, the US Navy’s aircraft carriers in the Pacific were America’s only force capable of offensive operations in early 1942. The carrier admirals wanted to be unleashed, if only to restore the Navy’s honor.

The new commander in the Pacific, Adm Chester Nimitz, knew something needed to be done but the four carriers were the only defense against a Japanese invasion of Hawaii. However by constraining them to Hawaiian waters they were also a target. On 11 Jan the Saratoga was torpedoed by a Japanese submarine, and only the heroic efforts of her crew kept her afloat. She would spend the next two months in dry dock in Washington, and out of the war: “a 25% reduction of America’s offensive combat power.” At the ardent behest of Halsey, Nimitz had made the decision, and the Saratoga sealed it: the carriers needed to attack something, anything. The air bases at the far eastern end of the Japanese Central Pacific perimeter offered an opportune target.

Under cover of escorting a convoy carrying a marine brigade to Samoa, Halsey and the Enterprise met Rear Adam Fletcher and the Yorktown, then in transit from the Atlantic. On 21 January, the two carriers and escorts sped off into the night to strike isolated Japanese air and sea bases in the Marshall and Gilbert islands, despite the threat from Japanese land based planes. It was a plan that, “was ‘daring’ if it worked, but ‘foolhardy’ if it didn’t.”

America’s first offensive of the Second World War started poorly and to much frustration for Halsey. Even before the Enterprise arrived off of Samoa, the limitations, and most importantly, the self-imposed constraints of peacetime training were glaringly obvious. Peacetime procedures were simply inadequate for wartime operations, even without enemy contact. Fatal accidents, friendly fire episodes, security breaches, flight delays, navigation errors, and logistics difficulties of all types were commonplace. According to Halsey, the US Navy “needed more of everything: more training, more gunnery practice, more anti-aircraft guns of every caliber, more ammunition, more torpedoes, more radios, more radar, more intelligence, more reconnaissance, more planes, more supplies, and more spare parts”. Refueling at sea was particularly cumbersome, and Halsey commented that “it took longer to get into action today than it did in 1812”.

On 31 January, Nimitz received confirmation from his code breakers that the Japanese carriers were in the Dutch East Indies, and gave Halsey and Fletcher the go ahead to extend their initial timelines and expand their targets. They were to “press home their attacks and work over the Japs”. On the night of 31 Jan/1 Feb, the American carriers parked themselves between the two largest Japanese air bases in the Central Pacific.

Around 5 am the two carriers launched their bombers, Halsey and the Enterprise’s against the Japanese bases in the Marshalls, and Fletcher and the Yorktown’s against the Gilberts. They were unescorted because there were not enough fighters to protect the fleet and escort the bombers at the same time.
Fortunately, the surprise was complete. It was a reverse Pearl Harbor, albeit on a much smaller scale. The dive and torpedo bombers neutralized both main air and sea bases, severely damaged several cruisers, and sank a plethora of merchant ships. The ineffectual previous generation Japanese Claude and Nate fighters were swept from the sky by the few American fighters that got into battle, while the carrier’s escorts made high speed runs to fire at targets from off shore.

For seven hours, the American crews listened to the radio transmissions and pilot chatter of the bombing raids with the undisguised glee of football fans listening to their team winning the big game. About noon, some of the pilots and senior officers began to wonder if they were pushing their luck. They were within easy reach of at least nine Japanese air bases (and maybe more) in various states of destruction, and surely every Japanese submarine in a thousand miles was heading for them.
At one pm, the ops officer from the squadron “Bombing Six” came back from his third run that morning and confronted Halsey, “Admiral, don’t you think it’s time we got the hell out of here?” He replied, “I’ve been thinking the same thing myself”.

The carriers recovered their aircraft and forty five minutes later were heading back to Pearl.

The strikes on the Marshall and Gilbert Islands shocked the Japanese. The events since 7 December were a nearly unbroken string of victories; this was the first time the US Navy fought back effectively. Moreover, just two months into the war, the flawed premises of the General Staff’s perimeter defense strategy were exposed. The physical damage was temporary and repaired quickly, but only because there were no follow up landings. The far flung bases were not mutually supporting and the Japanese did not have enough carriers to cover the entire perimeter. Yamamoto quipped that, “We will have to dictate peace terms from inside the White House”.

But first things first: he needed to destroy those carriers, even at the expense of ongoing operations. The experience they gained on the raids was invaluable and they were now even more dangerous. Yamamoto needed a suitable target to lure them out and destroy them. That target was Hawaii, more specifically the last stepping stone before the invasion of Hawaii:

Midway Island.