The only reason the Americans finally dropped the idea was the power of the British navy which, incidentally, our last half dozen governments have destroyed.
The film below lasts 45 minutes and is absolutely riveting. When I was sent a link I just couldn't put it down. Make sure you have the time before watching it as it is impossible to put down.
My readers from Britain, Canada, and the ANZAC countries should watch and thank their lucky stars it never happened as the death toll could have been as bad as the first world war.
The story is also in Wikipedia.