After returning to the United States in August 1944, he was named commander of the 314th Bomb Wing (Very Heavy) and promoted to brigadier general in January 1945. Power moved his B-29s to Guam in December 1944 as part of the 21st Bomber Command. From Guam, he directed the first large-scale fire bomb raid on Tokyo, Japan, on March 9, 1945. In a command aircraft, flying back and forth over Tokyo during the attack, Power was deeply impressed by the inferno of destruction playing out thousands of feet below. He later commented, "True there is no room for emotions in war . . but the destruction I witnessed that night over Tokyo was so overwhelming that it left a tremendous and lasting impression on me."