Probably apocryphal, but I'm sure there were similar conversations. Though from what I've read, many in the Japanese High Command were fully aware of the disparity in war-making potential between the U.S. and Japan. That Japan decided to go to war anyways despite knowing this is still discussed.

There's a page over on combinedfleet.com (great resource and discussion) that goes into the numbers, and it's truly astonishing. U.S. output could be described as terrifying. http://www.combinedfleet.com/economic.htm