There are so many reasons. 1. When you basically own a printing press (i.e. the Federal Reserve) why would you need to launder anything? 2. American arms manufacturers got most of that money. 3. There are several places in the US to launder, they don't need to do that through Eastern Eruope. 4. This war is strategically and ideologically very important to the US.....I could go on...but I think you get the picture.