If the United States adopted Lancaster instead of its wartime bombers

What if the United States built Lancaster bombers instead of the B-17, B-24, and B-25?

Earlier British airframes and engines would be needed, and the prospective reduction in American losses is disputed: aircraft performance would improve some operations while daylight doctrine would remain a danger.

American Lancaster production in the late 1930s would require an earlier British development path for the Wellington, Manchester, and Merlin engine. British willingness to release an advanced bomber design is disputed, with private ownership of Avro and Rolls-Royce offered as a reason a sale could still occur. One objection is that the Lancaster might lack the range the United States wanted. Foxo expects fewer American deaths in European operations because of its performance and ability to navigate effectively, but that claim draws immediate qualifications. The B-17's higher ceiling is raised in reply, followed by a distinction between maximum altitude and altitude attainable with a load. Others expect American daylight-bombing doctrine to continue causing heavy losses regardless of the aircraft. Earlier Merlin development also raises the possibility of 2,000-horsepower Griffon engines reaching British fighters and naval aviation before the war.