I imagine that it had to do with a number of dynamic factors. Here's some in no particular order:
-- If Russia beat Germany while we were fighting in the Pacific, we'd have more problems down the road if they decided they didn't want to leave the countries they invaded(which was a real possibility, and despite our being allied with them we didn't trust them at all).
-- Political pressures from England demanded that we help them first.
-- A-Bomb race with Germany.
-- Freeing Europe from the German threat would free up non-US allied troops to help in the pacific(after all, would the UK fight in the Pacific just because we asked while thier cities were being bombed?)
-- It bought us time to develope the A-Bomb and use it without fear of pissing off our European Allies who live next door to ground zero in Germany.
-- American interests were under a lower direct threat in the Pacific after the initial Japanese land grab.
-- More Americans in power were(and are) of European descent, and had greater interest(both economic and cultural) in seeing Europe freed.
-- Britan was under direct threat from Germany, and if Britan fell we'd have a hell of a fight trying to get a toehold in Europe.
-- We(American Mainland) were not really under direct threat from Japan, as far as I can tell. We may or may not have been under direct threat of Germany, but it seems like it was perceived that we were.
There's probably more, and I may add to this. If any seem wrong, feel free to critique this list. Keep in mind that it's 6am, and I have had insomnia for the last two nights, so please go easy on my first attempt at in depth discussion on this board.
[This message has been edited by Doctor (edited 09-14-2000).]