Of course, it depends on Congress, which won't do anything like that. If the US were responsible for 20% of that, obviously it would be $15.6 trillion, which over 25.5 years is $624 billion a year. The much lauded "climate bill" Congress passed a couple years back allocates $37 billion a year, so we're 17x "short".
This stuff annoys me for some reason, or entertains me, one or the other.