Economists argue that the U.S. was not able to hit the president's 70% vaccination goal until the 4^th of July, 2021 can partly be explained by economic epidemiology. Based on the economic interpretation of epidemic, explain whether you agree or disagree with the president's statement "with enough vaccine supply, we will return to normal by the end of 2022" and provide the economic reason why you think that way. Limit your answer to 5 or fewer sentences.