In 19 forty five, plenty of battleships have been sunk by aircraft up to the point we are in the story right now. The ships and their crews were not unduly concerned about going off without air cover. They had every right to be considering the amount of anti aircraft weaponry these ships were loaded with. But here's the dirty little secret about it all: enough planes always get through so that you can't defend these ships alone.
Japan's rising sun goes supernova and engulfs a huge area of Asia and the Pacific. A war without mercy begins to develop infusing the whole conflict with a savage vibe.