Editor’s Note: The following is the third in a series of excerpts adapted from Victor Davis Hanson’s new book The Second World Wars. It appears here with permission.
Over 2,400 years ago, the historian Thucydides had emphasized the military advantages of sea powers, particularly their ability to control commerce and move troops. Not much had changed since antiquity, as the oceans likewise mattered a great deal to the six major belligerents in World War II. Three great powers were invaded during the war: Germany, Italy, and Russia. Three were not: America, Britain, and Japan. All the former were on the European landmass, the latter were either islands or distant and bounded by two vast oceans. Amphibious operations originating on the high seas were a far more difficult matter than crossing borders, or in the case of Italy, crossing from Sicily onto the mainland. The protection afforded Great Britain and the United States by surrounding seas meant that containing the German threat was never the existential challenge for them that it always was for the Western Europeans. The generals of the French may have always appeared cranky to the Anglo-Americans, but then, neither Britain nor America had a common border with Germany. The only way for Germany to strike Britain was to invade and occupy the French and Belgian coasts, as reflected both in the German Septemberprogramm of 1914 and in Hitler’s obsessions with the Atlantic ports between 1940 and 1945. Since the 15th century, European countries that faced the Atlantic had natural advantages over those whose chief home ports were confined to the North, Baltic, and Mediterranean Seas.
Even if weaker than Germany, the islands of Japan nevertheless made an Allied invasion a far more difficult proposition than would crossing the Rhine or Oder into Germany. In fact, no modern power had ever completed a successful invasion of the Japanese homeland, a fact well known to Allied planners who wished to, and did, avoid the prospect through dominant air power.
Japan’s various strategic choices in 1941 were predicated a great deal on traditional geographical considerations. Japan could further reinforce its decade-long presence in China, or in June 1941 join Hitler by attacking the Soviet Union from the east, or absorb more orphaned colonial territory in Asia and the Pacific, or allow the Imperial Navy to begin new wars against the United States and Britain because it was an island sea power with few immediate worries about ground invasions or enemy amphibious landings. Left unspoken was the fact that in almost all these geographical scenarios, an often xenophobic and resource-hungry Japan had few friends. It had alienated the Western powers during the 1930s, invaded China in 1937, fought the Soviets in 1939, and been aggressive toward India; it was disliked and distrusted in the Pacific and unable to partner effectively with its own Axis allies.
Any eastward expansion of 20th century Japan into the Pacific depended also on the status of its western geography. If either Russia or China were to be hostile — and both usually were — by definition Japan would be faced with an uninviting two-front war. In World War II, the bulk of Japanese ground forces — over 600,000 at any given time — was fighting in China, where over a half-million Japanese soldiers eventually perished. Japan was willing to risk a two-front war after its nonaggression pact with the Soviet Union in April 1941, given that the Chinese front was mostly stalemated, but it never envisioned the possibility that Pearl Harbor would lead to a three-theater conflict in which Japan would be fighting China, the United States, and finally the Russians. Because pulling out of the Chinese morass was deemed unacceptable by the government of General and Prime Minister Hideki Tojo, and given that the Imperial Japanese Army had already fared poorly against the Russians from 1932 to 1939 along the Mongolian border, Japan felt its best choice of aggression was a surprise “preemptory” naval air attack on the geographically distant Americans, who allegedly might soon have attacked Japan or would eventually have strangled its importation of key resources. General Tojo told the Japanese war cabinet that he had thought of all the alternatives “until it makes my head ache, but the conclusion always is that war is unavoidable.”