I knew about Opal and that they helped build up the Nazi war machine, but I did not realize they were such a large part of it. I remember reading that in the late 1940s, GM received several billion dollars in reperations from the US government for the damange caused to their Opal factories during the allied bombing of Germany. Yes, you read that right....our government apoligized and paid reparations for damange done when we bombed factories that made Nazi war vehicles.