I think that the basics are this: winning is better, because winning begets winning, but there's no need for hand-wringing or gloom, because losing doesn't put us, in terms of how things look on paper, in that much worse of a position.
Columbia looked awful today, James is carrying an injury, and they couldn't stop giving the ball away. I'm not sure that Japan was all that much easier/harder, whichever way you want to look at it.