When Martin Caidin wrote his great science fiction thriller, Cyborg, the best TV producers could do for an alternate title for the series they made it into was "Six Million Dollar Man." So incredibly, mind-searingly, stomach-churningly lame. How it became a hit I can't imagine.
Of course the only time they seriously altered past Earth history, Joan Collins lived to star in Dynasty and the Federation disappeared and no one ever saw William Shatner again.
This movie always stuck with me. A colorful but lightweight movie because obviously it didn't happen. The same reason Gene Roddenberry kept getting overruled when he wanted the Enterprise and go back and savce JFK from assassination: it cannot succeed - in this timeline. TFC was a fun speculation, but lightweight because nothing really happened, or coule be allowed to happen. The speculation on the ultimate use of the ship is excellenbt. Question: what would've been the political response to the Nimitz saving Pearl Harbor from the Japanese air attack? Would the isolationist movement have hampered the response since the attack didn't come which united the Americans into a crusade agains the Axis? Would Hitler have declared war a few days later against the US after realizing there was no chance the Japanese would survive the situation now presented, much less be in position attack Russia, considered his motive foir declaring war? What kind of peace would've been sought from Japan which was still laying waste to the Chiniese (whose relations with Japan remain cool today; they don't have MTV-conditioned memories of the war like we do and they lost millions of people).