Lol, China would be least bit worried if the 7th fleet moves to BD, in fact they might welcome the move. It means, not only will there be less American presence in Japan and hence less threat to China, but all that American muscle will now bother India. Its a total win for China if the authors wet dream does come true. BD is no where near the Chinese coast line for them to be bothered if the 7th fleet moves there.It'd cause China and India to **** bricks too.
It's technically not possible for the entire 7th fleet to be based in BD.