That had less to do with our manufacturing capabilities than with the fact that the Atlantic Ocean separated us from Europe. Our manufacturing capabilities weren't necessarily greater than Germany's -- we just didn't have to worry about our factories having bombs dropped on them every other night.
The age of the ICBM pretty much made that "advantage of geographic separation" pointless. In fact, it's kind of neat how an enemy of the United States today would have to drop bombs on China, Indonesia, and Malaysia in order to hamper our manufacturing capabilities.
They don't have to do that. Once we've sold out our industrial base to foreign countries for a quick buck and are dependent on those countries to sell us military hardware (stuff that we probably invented in the first place), all an enemy of the US has to do is go to those countries and "convince" them that it isn't "in their interest" to sell us that stuff anymore.
When that is done, what are we gonna do? Send our country of lawyers out to bombard the enemy with lawsuits? Send the burger flippers from Mac's out to throw their spatulas at the enemy? Not send them anymore IOUs? That'll sure scare 'em...
Unless, of course, that enemy is China, Indonesia, or Malaysia, in which case, we are series FUBARed.
The problem with having our mfg. in China Indonesia and malaysia is that China is an enemy and Indo. and Malay. are not too far behind being strong Muzzie states.