Why did Adolf Hitler Declare War on the United States?

The essential mystery of World War II was why Adolf Hitler on December 11, 1941, declared war on the United States.  The action is incomprehensible and inexplicable from a rational and strategic point of view, and would ultimately lead to the defeat of Nazi Germany and the suicide of Hitler. The context should have been a warning. Objective factors were that at the time Germany had a population of 86 million, the U.S. had 146 million. Germany had a GDP of $412 billion; the U.S. had $1.1 trillion. Germany had three million military; the U.S. had 17,000 full time soldiers.

It may be inconsequential but it is diverting  to consider the countless times and the unforeseen consequences when history might have changed if events had or had not taken place. What if President Abraham Lincoln had not gone to the Ford’s theater on April 14, 1865, what if the Archduke Franz Ferdinand had not been assassinated in Sarajevo in June 1914,what if Guy Fawkes had succeeded in assassinating King James I, blowing up Parliament, and returning  the country to Roman Catholicism, what if the Academy of Fine Arts in Vienna had not rejected Adolf Hitler’s application for admission to the school, what if Napoleon had won the Battle of Waterloo, what if George Washington had not crossed the Delaware?

“The die is cast,” said Julius Caesar when he crossed the Rubicon, the river, on January 10, 49 BC, breaking the law and making military conflict against Pompey and the Roman Senate  inevitable. The law was that entering the land of Italy with a standing army was treason.  Caesar, who was governor of the province of Gaul, now France, had defied the ultimatum by the Senate which viewed him as threat, not to march south but to disband him army and return to Rome.  Caesar marched, became virtual dictator, but forget to be aware of the Ides of March on March 15, 44 BC when he was assassinated.

Caesar thought he was invulnerable, intoxicated by success, and his actions can be said to be logical from his own point of view. and even the last act of his drama could be understood and anticipated. It is more puzzling to understand the motives of  the rulers and tyrants of 20th century Europe in Germany, Italy and Japan, and the reasons for their actions may be questioned today.

it is not incongruous to argue that World War II was certain to be won by the Western Allies because Adolf Hitler declared war on the U.S. four days after the Japanese bombing of Pearl Harbor and the destruction of much of the U.S. Pacific fleet on December 7, 1941. The event dramatically transformed the separate European and Asian wars into a World War.

On October 25, 1936, the Rome-Berlin Axis between the two countries was announced. A month later, November 25, 1936, Japan joined with Germany in the Anti-Comintern Pact, one against the Communist International, but specifically against the Soviet Union. Italy signed it on November 6, 1937, thus linking the three countries. However, the relationships were more complex because of two events: the German-Soviet nonaggression pact of August 23, 1939; and the invasion, a few days later, September 1, 1939, of Poland by Germany, the actual start of the European war.

It is enticing to reflect on the motives of the Axis leaders and the relations between the countries. The Tripartite Pact, signed on September 27, 1940, in Berlin, by Ribbentrop, Italian foreign minister Galeazzo Ciano and Japanese Ambassador Saburo Kurusu, called for the three countries to assist one another with political, economic, and military means, when one of them was attacked by a power then not involved in the European war, or in the Sino-Japanese conflict. This excluded the Soviet Union which was not directly involved in either of them. However, the Pact was implicitly though not legally directed against the U.S. However, what is particularly relevant is that  there was no military agreement between Germany and Italy on one hand and Japan on the other  to support each other if one was at war with any other country.

When Nazi Germany launched Operation Barbarossa against the Soviet Union on June 22, 1941, Japan which had a neutrality pact with the Soviet Union of April 1941 did not support it. The various conflicts only became a global one when Hitler decided to declare war on the U.S.  The crucial question is why did he do this? Germany was already involved in conflict with the Soviet Union since June 22, 1941, and mistakenly believed the Russians would completely collapse.

No doubt Hitler had long thought of dealing with the U.S. lest it challenge Nazi Germany though it was not a key priority. For security reasons,however, Germany was developing long range bombers, capable of reaching New York, and  building  battleships with heavy armament to destroy U.S. ships. Yet  the main strategic priority for Hitler appeared to be the Soviet Union. But in the Eastern war he was deluded, before the offensive had stalled, and he thought that the Soviet Union would be quickly beaten, or that it would collapse from lack of domestic support for Stalin.  He could not have anticipated the early arrival of bad weather in Russia or the fierce resistance of Russian troops, or the scorched earth policy or the burning of crops and destruction of bridges.  He may have believed that Japan, whose interests in East Asia clashed with U.S., British, and French interests, and was occupying French Indochina, had delivered a knockout blow on the U.S.  Hitler was not given notice by Japan of its attack. Nevertheless, on December 8, Hitler ordered his navy to sink ships of the U.S. and its allies.

Japan may have acted on Pearl Harbor because of its belief that the U.S. Pacific fleet was interfering with its planned military actions in southeast Asia against so-called western controlled territory. On December 7, 1941, Japan struck the naval base at Pearl Harbor with hundreds of fighter planes that destroyed or damaged 20 U.S. naval vessels, including eight battleships and over 300 planes. More than 2,400 U.S. individuals died, and 1,000 were injured.

President F.D. Roosevelt asked Congress to declare war on Japan, and delivered his “Day of infamy“ speech. On December 8, the Senate, 82-0, declared war, and the House did so by 388-1, with  a pacifist,  Jeanette Rankin of Montana ,the only negative vote. The first response was from Italian dictator Benito Mussolini who, in a declaration from the balcony over the Piazza Venezia in Rome pledged “the powers of the pact of steel” against the U.S.

On the same day Japanese  Ambassador Oshima  in Berlin called on foreign minister Ribbentrop to get Germany to declare war on the U.S. Ribbentrop stalled in light of the Tripartite Pact of  September 27, 1940 which said  that Germany and Italy would militarily support Japan if it was attacked, but avoided the question if Japan was the aggressor. But Hitler in his speech to the Reichstag on December 11, 1941, declared war on the U.S.

Hitler argued that Roosevelt was the real cause of the war because of the failure of the New Deal. He said the president, supported by “plutocrats and Jews,”  tried to cover up his economic failure.  First he incited war, falsified the causes, then wrapped  himself in a cloak of Christian hypocrisy and slowly but surely leads mankind to war, “not without calling god  to witness the honesty of his attack in the approved manner of an old freemason.” Germany, Italy, and Japan would after victory, continue in closest co-operation to establish a new and just order. The Axis powers would win because the U.S. would be preoccupied with Japan, while Germany would continue its conquest of the Soviet Union.

In all this Hitler underestimated American resouces and American will to fight once public opinion had changed to oppose Hitler, overestimated the threat of Japan to deliver a fatal blow to the U.S.  The fundamental irony is that Japan’s attack was the prelude to concerted action by the U.S. and Allied powers to destroy the Nazi regime. .

Yet, the two questions remain. Why did Japan attack Pearl Harbor, and why did Adolf Hitler declare war on the U.S.?