The early months of World War II were a time of high anxiety over inexperienced personnel, critical shortages of supply, and great uncertainty as to strategy. “Defense” was the operative word of the day. But while many in the American military worried about how they would defend the United States, Admiral Ernest J. King, commander in chief of the U.S. Fleet, seized on how they might attack its enemies.

As the Joint Chiefs of Staff wrestled with how to prioritize the demands of a two-ocean, global war, Admiral King was adamant that the West Coast–Hawaii–Australia sea-lanes remain in American control at all costs. These routes ran past islands most Americans had never heard of: Samoa, Fiji, the New Hebrides, and New Caledonia. If the Japanese gained a toehold on any of them, they would push a bulge of military influence well eastward into the South Pacific—at best detouring support for Australia and at worst severing these lines. With limited resources, just how, Army Chief of Staff George C. Marshall asked King, did the admiral propose to defend this critical corridor?

“The general scheme or concept of operations,” King wrote in his February 1942 reply, “is not only to protect the lines of communications with Australia but, in so doing, to set up ‘strong points’ from which a step-by-step general advance can be made.” General Marshall immediately questioned the words “general advance.” The Japanese were rushing toward Australia, British Prime Minister Winston Churchill was bemoaning the fall of Singapore as akin to the end of Western civilization, and both Churchill and President Franklin Roosevelt had just agreed to concentrate on defeating Germany first. How could King even consider a “general advance” against the Japanese in the Pacific?

But King was emphatic about how he could and would accomplish it. Using marines as the spear point, King proposed to occupy strategic positions along the West Coast–Australian lifeline from which to strike toward Japan. King repeated his plan for President Roosevelt and urged that with limited resources and an almost unlimited geography over which to fight, the United States should determine on “a very few [King’s italics] lines of military endeavor and concentrate our efforts on these lines.”

For King, the most important line of the “very few” in the Pacific was to secure Samoa, Fiji, and New Caledonia as strong points along the West Coast–Hawaii–Australia lifeline and then drive northwest from there into the Solomon Islands, including an island called Guadalcanal. “Such a line of operations will be offensive rather than passive,” King maintained, “and will draw Japanese forces there to oppose it, thus relieving pressure elsewhere.”

Thus, King’s operational strategy for offensive operations in the Pacific—as opposed to mere defensive containment—was adopted even as the American navy still reeled from the blows of Pearl Harbor. “It will be a long and hard war,” King admonished, “but it is high time to stop talking defense—and above all to stop thinking defense.”

But even as King prepared to go on the offensive, the Japanese were consolidating their hold on the Solomon Islands. If they succeeded in establishing strong airfields there, this airpower would threaten the heart of the West Coast–Australia sea-lanes. When the Japanese began to construct a seaplane base on the tiny island of Tulagi just north of Guadalcanal in May 1942, King knew such action required an immediate response. King argued that the seaplane base at Tulagi had to be captured in a matter of weeks. General Marshall and the army wanted to postpone any invasion of the Solomon Islands three to four months. King snorted and supposedly replied, “If we were to wait until that time, every exact button of their gaiters would be buttoned up.”

When King received intelligence reports that Japanese construction battalions had landed on Guadalcanal and were constructing an airfield, King ordered that both Tulagi and Guadalcanal be captured before any Japanese airfield became operational—quite possibly within a month. The clock was ticking. King picked an assault date of no later than August 1, 1942. Everything was in short supply. There was a frantic rush of men and materiel; coordination between ship and shore commands was still in its infancy; and even the veteran First Marine Division had yet to make an amphibious landing under enemy fire.

There were a thousand excuses why it couldn’t be done, but King was determined to stick with the schedule. His only concession was begrudgingly to move the assault back one week. So on August 7, 1942, the first of sixteen thousand marines splashed ashore to moderate resistance on Tulagi and initial light resistance on Guadalcanal. One day later, they succeeded in capturing the uncompleted airfield, soon renamed Henderson Field in honor of a fallen marine aviator.

But that was just the beginning of the fight. On August 9, the US Navy suffered one of its worst defeats at the Battle of Savo Island. The Australian cruiser, Canberra, and three American cruisers were lost and another heavily damaged. But King would not abandon the fight. “No fighter ever won his fight by covering up—by merely fending off the other fellow’s blows,” King said. “The winner hits and keeps on hitting even though he has to take some stiff blows in order to be able to keep on hitting.”

It took four months of bitter fighting before Guadalcanal was secure and the Japanese abandoned their efforts to re-capture it. King’s strategy of taking the offensive to protect the West Coast–Australia sea-lanes had worked after a frightful cost—twelve hundred American marines lay dead on Guadalcanal and upwards of four thousand American sailors rested beneath the surrounding waters after six major naval surface battles and countless air-to-sea actions. But the tide had turned. As King had predicted, taking the offensive and concentrating on a “very few” lines of military engagement had drawn Japanese military strength to a focal point where America’s limited resources could be brought to bear. The best defense had indeed been a bold offense.