The DIFFERENCES between Russia and the United States affected Germany's strategy, not the total of the two. Germany put more resources into fighting Russia because Russia was likely to much worse on Germany than the US- that is how bad Germany was on Russia early in the war.

On April 3, 1917 the United States declared war on Germany. Germany was well aware that it would take many months, perhaps a year, before the US armed forces would be able to participate effectively. However, the US represented a major danger. They were fresh, with a population unaffected by the devastating war, and in huge numbers. In October, 1917 the Russian Revolution toppled the government of Russia. Lenin, a former German resident, signed a peace with Germany in March, 1918 in order to consolidate power at home. Thus, Germany had a golden opportunity to decide the war if they acted quickly. The peace with Russia allowed dozens of German divisions to relocate to the western front before the US was present in war winning numbers. These reinforcements made it possible for Erich Ludendorff, CinC of the Western Front to launch Operation Michael on March 21,1918. Operation Michael was a last ditch, all-or-nothing offensive to break the English and French armies before the exhausted Germans were overwhelmed by allied numerical superiority. Ultimately, Germany lost the gamble and the allies proved already too strong to defeat.