If America had not started to massively support the UK with military equipment beginning september 1940, Hitler would never had declared war against America.
So why did America start help the UK against Germany’s relentless assaults?
Because America is a civilized nation and knows how to show respect to its fathers and forefathers which were all mostly english. A family is a family. I respect family values.
You should ask FDR. He's the one who authorized it, but if I was to take a guess, and I've already said it in one of my other comments to you, that lend-lease was the first choice rather than sending American troops to fight and die again in Europe. December 7th, 1941 changed all of that.