... broke the back of the defense of Tinian. With their communications shattered by sustained fire from Saipan and increasing fire from Tinian itself ... the survivors were capable of only the weakest, most dazed sort of resistance.... Now and again during the next seven days, small groups took advantage of the darkness to [launch night attacks], but for the most part they simply withdrew in no particular order until there remained nowhere to withdraw.
That was a common judgment after the Tinian battle had ended. But at the time, according to the 4th Division intelligence officer, Lieutenant Colonel Gooderham McCormick, a Marine Reserve officer who later became mayor of Philadelphia, things were not so clear: “We still believed [after the counterattack] the enemy capable of a harder fight ... and from day to day during our advance expected a bitter fight that never materialized.”
Nevertheless, a lot of hard work lay ahead. One of the most demanding tasks was the simple but exhausting job of humping through cane fields in terrific heat, humidity, and frequent monsoon downpours, fearful not only of sniper fire, mines, or booby traps, but fearful as well of fires that could sweep through the cane fields, incinerating anyone in their path.
[Sidebar ([page 12])]:
Preparatory Strikes
No battle in the Pacific was a “piece of cake.” But there was less apprehension among the Americans about the outcome at Tinian than in any major operation of the war. Admiral Raymond A. Spruance later described it as “probably the most brilliantly conceived and executed amphibious operation of World War II.” Lieutenant General Holland M. Smith, commander of the Expeditionary Troops during the seizure of the Marianas, called it “the perfect amphibious operation.”
It took place under optimal conditions for success. The small Japanese garrison on the island had no hope of relief, resupply, escape, or victory. Three miles away, across the narrow Saipan Channel, three battle-tested American divisions—more than 50,000 men—were available for the inevitable invasion. For seven weeks the bombardment from U.S. air and sea armadas, joined by the big guns on Saipan, had been relentless, day and night.
The effect on Tinian’s civilian inhabitants was recorded by James L. Underhill, later a Marine lieutenant general, who became the island’s military commander at the end of the battle:
The state of these people was indescribable. They came in with no possessions except the rags on their backs. They had been under a two-month intense bombardment and shelling and many were suffering from shell shock.... They had existed on very scant rations for six weeks and for the past week had had practically nothing to eat. They had been cut off from their own water supply for a week and had caught what rainwater they could in bowls and cans. Hundreds of them were wounded and some of their wounds were gangrenous. Beri beri, syphilis, pneumonia, dysentery, and tuberculosis were common. [They needed] shelter, food, water, clothing, medical care, and sanitation.
The bombardment began on 11 June—four days before the Saipan invasion—when carrier planes from Vice Admiral Marc A. Mitscher’s Task Force 58 launched a three-and-a-half day pummeling of all the principal Mariana Islands. A fighter sweep on the first day, carried out by 225 Grumman Hellcats, destroyed about 150 Japanese aircraft and ensured American control of the skies over the islands.