Rear, then Vice Admiral Frank Jack Fletcher:
en.wikipedia.org
Commander of American carrier forces at Coral Sea, Midway and the Eastern Solomons, he was beached in September 1942 for reported mistakes during the Guadalcanal landings (not covering Turner and thus enabling 1st Savo Island), and during the last of the aforementioned three battles where, according to our favourite CNO Ernest King, he failed to ensure a complete American victory. However, by that point he was one of the most experienced American admirals and had accounted for four fleet carriers and two light carriers. His departure meant that TF 61 in October would be commanded by Thomas C. Kinkaid, who lost Santa Cruz and the valuable
Hornet, and thereby nearly the entire campaign.
Your challenge, therefore, is to keep Fletcher in command of American carrier forces during the entirety of the Guadalcanal campaign. You may use any POD you like. For bonus points, what consequences do you think there would be?