Island Hopping in the Pacific – WWII

The old English proverb, “necessity is the mother of invention” could easily be applied to the armed forces of the United States in the Pacific during WWII.  This necessity was brought about due to the overarching American strategy of “Defeat Hitler first”.  The reasons for this are complex and highly speculative.  What we do know is that upwards of 60-70% of all wartime resources were allocated for Europe.

Given these priorities, the United States Navy and Marines were compelled to invent a new type of warfare.  A warfare that was dictated by the geography of the Pacific.  By April of 1942, it was clear that the Japanese had successfully captured much of the key islands in the South Pacific.  Army General Douglas MacArthur and Navy Admiral Chester Nimitz along with Admiral William “Bull” Halsey devised a plan unique in the annuls of military history.  They would orchestrate a series of complex maneuvers that has come to be known as “island hopping”.

The purpose of this plan was to attack islands that were not as strongly defended by the Japanese.  Once under United States control, the island would be fortified and used as a staging area for the next attack.  By skipping over heavily defended islands, allowing them to “wither on the vine”, the U.S. forces would be able to advance closer and closer to their ultimate objective.  The home islands of Japan.

While ultimately successful, this warfare was costly.  Guerilla warfare was new to the men who fought in the Pacific.  Their enemy, enamored with the Code of Bushido, was alien as well.  This code encouraged fighting to the death and not taking prisoners.  Another challenge was clearly the geography.  Jungle fighting on hilly terrain coupled with heat and humidity lent itself to a host of issues.  Diseases such as malaria, dysentery and skin funguses plagued soldiers throughout the Pacific.Japanese advances in the Pacific.

As the war progressed and the American military was able to advance across the Pacific, the fighting became more vicious.  The penultimate battle of the war took place in February of 1945 on the island of Iwo Jima.  What made this engagement so significant was it was the first time that the United States was fighting the Japanese on ancestral Japanese soil.  All the other battles had been on islands that the Japanese had conquered.  Not Iwo Jima.  The ferocity by which the Japanese defended this island was unlike anything the United States military had seen.  Over 23,000 Japanese soldiers were ensconced on the island prior to the invasion.  Over 21,000 died in its defense.  These numbers would be eclipsed several months later during the largest battle of the Pacific war.  Okinawa was another ancestral Japanese island.  The difference was the scale.  Iwo Jima was a rocky outcropping with a volcanic mountain (Mt. Suribcahi) and no civilian population.  Okinawa is a very large island with a sizable population.  By the time the battle had ceased, over 100,000 Japanese soldiers and civilians were killed.

The cost of the war, in terms of human life, weighed heavily President Harry Truman.  When the casualty figures came in from the final two battles on Iwo Jima and Okinawa the president was stunned.  Most historians point to these battles as the tipping point in convincing Truman to the wisdom of dropping the atomic bombs on Hiroshima and Nagasaki in August of 1945.

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