If America concentrates on Japan before Germany

How would the war change if the United States concentrated on Japan rather than Germany?

Britain could blockade and contain Germany, but major European invasions would be delayed while Allied strength concentrated on Japan.

Operation Torch would probably disappear because American personnel and resources made the historical landing possible. Britain would continue the North African campaign from the east and might still take Sicily after stabilising the Mediterranean. Without American mass, however, a 1944 cross-Channel invasion becomes unlikely. British sea power could sustain blockade and containment while forces shifted through the Mediterranean toward the Eastern Fleet and the war against Japan. Germany would probably face a later British-led return to Europe after Japan had been defeated or contained, reversing the historical order of Allied concentration.