Plan Orange

What if Japan had not attacked Pearl Harbor and instead had attacked the Philippines where the United States had suspected they would attack. This action by Japan would have caused the United States to enact Plan Orange the United States' plan to deal with an attack by Japan against her far east possessions. Japan would have used its knowledge of America's Plan Orange, for Japanese naval officers had knowledge of this plan, to stage hit and run carrier and submarine attacks on the American fleet as it went to aid the Philippines, weakening the American Pacific fleet and then they planned to engage them in a decisive naval battle in which they, the Japanese had the advantage. What if in this battle the major elements of the American Pacific fleet had been lost i.e. the carriers and battleships, unlike in Pearl Harbor these ships would have had no chance of being salvaged, and Japan's navy would have had unrivaled supremacy for even longer. Would this have had a extreme effect on the outcome of the pacific war? or just prolonged the inevitable defeat of Japan?

I personally believe the latter, despite the more breathing time Japan would have acquired she could never have the capacity to invade the United States and that is what it would take to defeat the US.

 

Good idea. I would agree that the Japan could never conquer the United States. However, if the American fleet including the carriers was destroyed in the open ocean, Japan might have been able to force America to sign a peace treaty allowing Japan to maintain its reign over the Pacific which was its main objective anyway. But, I am not fully informed on whether this course of action for the Japanese would succeed.

 

First of all, your analysis of Plan Orange is badly flawed. Only the earliest versions of Plan Orange envisioned the American Fleet rushing headlong across the Pacific to engage the Japanese Fleet in a decisive battle somewhere in the western Pacific. In later versions of Plan Orange, cooler heads prevailed. A more mature Plan Orange provided for a slow and methodical advance across the Pacific, seizing and securing fleet and air bases as required to defend the fleet from Japanese attritional efforts, and ensuring that the US Fleet arrived in the western Pacific for the decisive battle in good shape and far stronger than the Japanese fleet. However, the Plan Orange of the 1920's, and early 1930's, wasn't even in effect in 1940-41.

By 1940, Plan Orange, which only envisioned a war between the US and Japan, had given way to the Rainbow war plans which took into account the effect of the European situation on US capabilities and priorities. Rainbow Five (WP 46) assumed that the US would be allied with Britain in a fight against the Axis (Germany and Italy), and that would take priority over the Pacific situation including the recovery of any US possessions lost to the Japanese. So the war plan in effect in 1941, when Pearl Harbor was attacked, had no provision for the defense (or recovery) of the Philippines and no plan for the US Pacific Fleet to move across the Pacific and attack the Japanese fleet. The US Pacific Fleet was to stand on the defensive in the Pacific and only launch major attacks on the Japanese if the Strategic Triangle (Alaska-Hawaii-Panama Canal), or the supply routes to Australia were threatened.

As for the Japanese knowing about the US war plans, they had no detailed knowledge of either War Plan Orange or Rainbow Five. They assumed the US Pacific Fleet would respond to any attack on US interests by moving west and intervening in Japanese operations in the western Pacific. In general, war Plan Orange did provide for this, but only on the US's time table. Rainbow Five did not provide for this at all, until the US had eliminated Germany, and built up it's fleet to overwhelming proportions. If Admiral Yamamoto had known of Rainbow Five, he undoubtedly would not have pushed for the very risky and dangerous attack on Pearl Harbor.

To sum up, the US had no intention of falling into a Japanese naval trap the way the Russians had at Tsushima in 1905. The fatal flaw in the Japanese "decisive battle" doctrine should have been quite obvious; it surrendered the initiative to the US which planned to wait until it was so powerful that no conceivable Japanese naval force had any chance to stand against it. Accordingly, no Japanese attack on the Philippines would trigger a response that would give the Japanese any chance of prevailing over the US fleet; your scenario had no chance of ever happening during WW II, and in fact was impossible from about the period of the mid-1920's when the internal debate about war Plan Orange was settled in favor of the cautious, methodical approach to defeating Japan in any Pacific war.

 

I was hoping someone with a better memory of Rainbow Five would reply. The Color Plans had been modified over the years until replaced by the Rainbow series, I just didn't recall when or by how much they had been altered.

Your post is exactly what I was trying to remember, the Defensive Triangle, the slow advance, and the USN's reluctance to engage the Japanese until they were doing so on their own terms. Thanks again.

 

What if Japan had only attacked other countries in the Far East and had avoided all American territories? Would the U.S. have still entered the war?

 

Very probably.

It wasn't so much the US possessions that concerned the American leadership (the US had voluntarily agreed in 1935 to give up it's only really significant possession in the western Pacific), but the fact of aggressive Japanese expansion in an area the US viewed as important to it's own commercial interests.

The US was willing to push Japan very hard on the issue of the Chinese war and institute crippling economic sanctions when Japan occupied positions in Indochina which allowed it to threaten direct military action against Malaya, Borneo, and the NEI. None of these events directly threatened the Philippines or Guam, yet the US was vitally interested and took what action it could short of military intervention. An overt armed attack on the NEI or British possessions would have had major negative repercussions on Britain in the European war, and it's difficult to imagine the US accepting this without a military response.

 

In addition to the post by DA, don't forget that Sec. of State Hull had made it clear in public speeches when Japan joined the Tri-Partite Pact, and occupied the colonies of Vichy France (French Indo-China) in 1940, that if Japan should attack the bases or holdings of the British or the Dutch, those nations would be given full access to all American naval and air bases in the South Pacific. This could only mean the Philippines, Guam, and Wake.

The Japanese knew this full well, so they could not ignore the American holdings in the area since they woud now be bases for any of the other western colonial powers they did attack. They had no choice but to launch offensives against the American holdings as well as the other nations holdings.