Japan and the Allies Summer-Fall 1941
The Japanese had invaded northern French Indochina in 1940 to cut off supplies to China from that source but this had triggered a host of economic sanctions by the US and Britain against Japan. Negotiations to improve relations had gotten nowhere in the last year, and as addition to the seizure of northern Indochina and ongoing war in China, the Japanese had signed a formal alliance with Italy and Germany that same year known as the Tripartite Pact. The German claim that the Americans attacked them first further worsens relations as the Japanese are forced to seriously consider immediate action to honor their alliance. A series of messages using the Purple Code from the Japanese Ambassador in Berlin relaying German requests for the Japanese to honor the pact which are subject to American monitoring due to successful code breaking, further make it clear to the United States that the Japanese almost certainly will act at some point.
The Japanese Army, once it becomes clear becomes clear that the bulk of the United States Navy is leaving the Pacific for Europe, decides to seize the remainder of French Indochina on July 24, 1941. The Army is encouraged by reports of massive German victories in the Soviet Union that continue to pour in. The pro-war elements of the Navy, led by the Naval Minister, firmly believe the Americans and British have the bulk of their navy unavailable for at least a year or more and it will be at least that time before the American Two Ocean Navy Act bears fruit. To the Army and prowar faction in the Navy, there is a narrow window to act to seize the Southern Resource Area and secure the Outer Perimeter against any American counterattack, and if the Germans continue to win, and knock the Soviet Union out, the Anglo-Americans will take years to defeat Germany, and might not even be able to launch that counterattack. Facing a bloody and expensive fight to bash through the proposed outer perimeter of island chains, the Americans will be already war weary when the Navy defeats them in a decisive Tsushima like clash somewhere near the Philippines or Marianas Islands, and thus having lost their fleet, the Americans will make peace.
This of course was magical thinking at the highest level but like so much of the Axis thinking in World War II was the basis for which plans were made and decisions acted on.
Meanwhile in the Washington Conference, in addition to discussing plans against Germany, Roosevelt and Churchill discuss what to do about the Japanese. Roosevelt makes it clear that while the Americans can fight to defend the Philippines and act alongside the British, his Administration cannot be seen as going to war with Japan to defend the British Empire. Thus Churchill will have to find forces to deter Japan that presumably will be available as the US Navy is heading to Britain to defend the British Isles against the Germans. The two men learned about the Japanese move into southern Indochina and have been waiting to discuss the matter jointly. On August 12, 1941, the United States, Britain, and the Free Dutch government announce an embargo on oil and gasoline exports to Japan, and in addition, the government of Britain and the United States freeze Japanese assets. With the press focusing on the War in Europe, this initially gains little notice although within a few days a few opponents in Congress ask questions about the increased sanctions but overall the general opinion in both American political parties is that even the reduced US Navy can handle anything the Japanese will throw at them and the Europeans can easily defend their empires against the second rate Japanese who have not even been able to defeat the Chinese yet. Indeed racist views of alleged Western superiority color Anglo-American thinking at every level and are at root to much of the early problems Allied forces had fighting the Japanese.
By September the Japanese Army is pressing for war and by October Hideki Tojo and Osami Nagano (Army and Navy Minister respectively) have forced the Prime Minister Konoe to resign and Tojo shortly after becomes Prime Minister. Even the faction of the Navy that is against war with the United States has accepted the inevitability and plans are now well advanced toward fighting that war. Although negotiations continue, they are clearly getting nowhere by November and it is clear that war has become inevitable. It is only a matter of time.
That time will end on December 8, 1941 (local time) in the Far East.
The War in the Atlantic and Europe
Meanwhile, the Soviets are suffering one massive disaster after another throughout July-September 1941, and the Western Allies are struggling to find a way to help them. The first convoy to Archanglesk (Operation Dervish) sails from Liverpool on August 21, and is not subject to German attention going or returning. Operations Gauntlet and Strength follow, evacuating Spitzbergen of civilians and carrying an RAF fighter group to help defend Murmansk, again with German interference. Several other convoys follow through the Fall of 1941, none of which receive enemy attention and the first US escorts are involved in November (PQ5). Indeed through the end of the year it looks like this route is surprisingly low risk.
In the Atlantic, the first German U-Boats arrive in July and find that while at war, the American coastal cities are still acting like peacetime. Air cover and convoys are still being organized and the first 21 Uboat patrols in July and August are wildly successful, sinking 45 ships, including 30 tankers in two months, and forcing the Canadians and British to send ships and aircraft to help, while Admiral Nimitz is finally able to get coastal convoys and naval air cover organized. He also presses for Army Air Force help and goes straight to Roosevelt asking for it. The President orders that 35 B17 C/Ds be transferred from the Army to the Navy, and while Hap Arnold grumbles, he does not fight too hard as those aircraft are viewed as stop gaps until the new B17E comes along. Better to lose aircraft to the Navy then squadrons and groups being diverted to a Navy mission. Another 60 B18 Bolo bombers are also transferred to the Navy in exchange for avoiding that mission in the future, and this nearly doubles the size of the Naval air strength available. Nimitz also orders 3 Navy dive bomber squadrons detached from the Fleet Carriers to assist while the Army planes are being transferred (and crews trained), while also some additional Catalina Flying Boats and eventually help from the Civil Air Patrol later in the year as it forms. With these efforts the initial slaughter is ended, and he is able to shift forces to the Caribbean and Gulf of Mexico when the Germans shift their efforts south as well. But the first six months after the US entry costs the Allies 2 million tons of shipping and the Germans only lose 22 U-Boats in return. The Uboat arm will call this the “Second Happy Time”.
It is not until late in the Fall that American coastal cities begin full scale black outs, and for a time American civilians are treated to burning ships on the horizon, oil slicks on the beaches and bodies and wreckage floating ashore. For the first time Americans realize that war is upon them in earnest. However there is a bright spot. The first Liberty Ship, the SS Patrick Henry, is launched on September 27 and many more will follow. The Americans also seize the French Liner Normandie, which is soon converted into an American troop ship (by the end of the year) while pressuring the Vichy government in the Caribbean to change sides to Free French, which gives the Americans access to the French carrier Bearn which is rapidly converted into an aircraft ferry.
In the Mediterranean, British warships fight their way to Malta on numerous occasions, reinforcing that beleaguered island, while the British complete their campaigns in East Africa and the Levant, securing their rear in Egypt. The US 24th Pursuit Group arrives in Egypt in October, with 90 P40C fighter aircraft, and is soon followed by 47th Bomb Group (A20) and 22nd Bomb Group (B26) in November. In October General Brereton forms the American Desert Air Force to work alongside the British Desert Air Force and begins flying sorties in November.
The British lose the carrier HMS Eagle in November near Gibraltar and soon after the battleship HMS Barham is also lost from German Uboats, but the demands of operations in the Atlantic prevent a more serious U-Boat deployment into the Mediterranean Sea. However this is offset by the British continuing to hold Tobruk and Malta, and a sharp rebuff to Rommel in the Western Desert, forcing him to retreat to El Agheila.
The biggest Anglo American effort however is Operation Chariot, also known as the St Nazaire raid in November 1941.