(2 of 3)
Scene of Action. Naval experts have long faced the fact that it is unsafe for a fleet to fight too far from its base, for unless ships can get back to their docks and repair shops, in case of damage, they are at the mercy of enemy submarines and air raiders. The naval rule of thumb for a safe operating radius for a fleet is 2,500 miles from its base. The only fleet operating base of the U. S. Navy in the Pacific is at Pearl Harbor, Hawaii. Only sketchy facilities for planes and light craft exist at other U. S.-owned islands. At Manila there are no adequate facilities for overhaul of cruisers and battleships.
For this reason, there has long been doubt that the U. S. Navy could ever force a decisive battle with the Japanese except in areas where it would be at serious disadvantage. For normally the Japanese, knowing the inferior weight of their fleet, would be careful to keep out of mid-Pacific, to fight only close to its own protected bases, where it would have the advantage.
In 1940, this long-accepted situation has been modified by events. War, if it comes, would now probably be set off by a Japanese attack on the Indies. This would move the scene of action some distance from Japanese as well as from U. S. bases. Such an attack would give the U. S. Britain and The Netherlands as allies, and provide the U. S. with the use of other bases—particularly the first-class British base at Singapore, secondarily the Dutch bases at Surabaya and Amboina, and the Australian base at Port Darwin.
Most logical spot for launching a Japanese drive to the south would be Japan's advance base at Formosa. Most likely main objective would be the island of Borneo, which has the oil supplies that Japan needs. Lightly held by Britain and The Netherlands, Borneo might seem easy to take. But between Formosa and Borneo lie 1,500 miles of water, over which Japan would have to stretch her supply line. Flanking the line are the great British fortress of Singapore, the lesser station at Hong Kong, the U. S. base at Cavite (Manila). Just beyond Borneo's southern tip lies the Dutch base at Surabaya.
British, Dutch and U. S. air and naval forces now in the Far East would be no match for the full power of the Japanese Fleet, but they would have more than a nuisance value. Based principally at Singapore, Britain has two cruisers, six to eight submarines, a considerable air force which can be reinforced by flights from Burma. At the Dutch bases are five cruisers, eight destroyers, 18 submarines and about 100 long-range bombers (some of them U. S.-made Martins). In the Far East the U. S. has two cruisers, 13 destroyers, twelve submarines besides patrol and bombing planes. Against an attenuated Japanese supply line they could play particular hell. To prevent this, Japan would probably be forced to give her cargo craft the support of her fleet, with the danger that the U. S. Fleet might cut it off from home.