Four salient features marked the planning for and the recapture of Corregidor Island.¹ First, unlike the situation in 1941-42 when MacArthur's forces held the island as a final fortress, Corregidor had no significant place in Japanese plans for the defense of Luzon. Second, planning was based upon intelligence estimates that reckoned the Japanese garrison at less than one-sixth of its actual strength. Third, the assault plan called for a parachute regiment to drop onto a small, rough area ill suited to such an undertaking. Fourth, the operation involved the most difficult of all modern military maneuvers--a co-ordinated parachute and amphibious attack, which had so far during the war met with only limited success.

Corregidor, logically the key to the defense of Manila Bay, was important to forces occupying Luzon only if the defenders elected to hold the strategically vital bay region. Thus, when Yamashita turned to a static defense in his mountain strongholds, the Japanese garrison on Corregidor became an isolated outpost of no strategic significance to him. Nevertheless, until the island was secured, the Japanese on Corregidor could harass Allied shipping within Manila Bay and could also use the island as a refuge for escapees from the mainland. Even if all military reasons for the early seizure of Corregidor could be brushed aside as of no moment, there still remained the matter of sentiment. Many officers at GHQ SWPA fervently awaited the recapture of "The Rock," and if it could be done dramatically--by means of a parachute drop, for instance--so much the better.

When MacArthur had outlined GHQ SWPA plans for securing Manila Bay to General Krueger, he had told the Sixth Army commander that those plans envisaged taking Corregidor by parachute drop, by amphibious assault, or by both. The final decision, the commander in chief went on, would await the results of an intensive aerial bombardment.² Upon receipt of this information on 3 February, the Sixth Army's G-3 Section quickly prepared a plan calling for the principal effort to be an airborne assault by the separate 503d Parachute RCT from Mindoro, where the regiment had been stationed since its landing on 15 December. Krueger's planners also proposed a nearly simultaneous and supporting shore-to-shore operation, to be conducted by a reinforced battalion of the 34th Infantry, 24th Division, from Mariveles, Bataan. The date of the attack was set for 16 February.

MacArthur approved the combined parachute-amphibious plan on 5 February,³ and simultaneously canceled his proposal to await the results of air bombardment--which had not yet begun in earnest--before deciding upon a definite course of action. Indeed, the Sixth Army's plan was prepared and approved so quickly as to suggest that planners were so familiar with the concept of the dual assault on Corregidor that only a bare hint was needed for a preconceived plan to become a reality.⁴

The decision to employ paratroopers to make the principal assault against an objective of Corregidor's size and terrain merits attention. Shaped like a tadpole, with its bulbous head pointing west toward the South China Sea, Corregidor is but three and a half miles long and one and a half miles across at its point of greatest width. (Map VII) The eastern--tail--section is sandy, wooded, and gently sloping, its highest point not much more than 150 feet above the bay. Near the center of the island, tunneled Malinta Hill rises abruptly to a height of some 350 feet, while immediately to the west the ground falls away just as steeply to a 500-yard-wide waist rising from sea level to a saddle about 100 feet high.

Known as Bottomside to the two generations of American soldiers who garrisoned Corregidor before World War II, the waist boasted small docks on both the north and the south and was the site of the demolished barrio of San Jose. Bottomside's sandy beaches provided good points for amphibious assault. Equally good and wider beaches were to be found along the tail section--it had been on the north shore of the tail that the Japanese had made their main assault in 1942.

West of Bottomside lay a gradually rising area known as Middleside, giving way on the west to steeper slopes leading to Topside, as the central portion of the tadpole's head was labeled. Covering a fairly even surface from 400 to 500 feet in height, Topside dropped precipitately to Manila Bay on the north, west, and south. Other than the slopes from Middleside, there were only two feasible approaches to Topside: James Ravine on the north and Cheney Ravine on the west, both easily defensible. Access to the western part of Middleside and to Topside's eastern slopes could also be had at Ramsay Ravine, at the southeast corner of the tadpole's head.

Topside is the key terrain feature on Corregidor, and against a defense centered there conquest of the island could be an extremely bloody affair. From Topside almost all logical sites for amphibious attack can be brought under fire, and even troops landing on the tail section, masked from flat trajectory fire by Malinta Hill, would be exposed once they tried to move past the hill toward Middleside and Topside. Amphibious assault at any point could prove costly, as the Japanese had learned in May 1942, when they had lost approximately half their initial assault force.⁵