IG Farben wasn't bombed because
A) most of the slave labour workforce were interned next to the plants, as the Germans were using the same "human shield" tactics Hamas uses now
B) Standard Oil of New Jersey had a 27 percent equity position in IG Farben's Lurgi process coal gasification plant operations, and were lessors of the carbon methanation process for fuel and lubricant synthesis to them (they received royalty payments uninterrupted throughout the war via a Belgium-domiciled firm from IG Farben) and
C) to have effectively bombed those plants would have eliminated any reason whatever to keep the Jewish, Russian POW and miscellaneous civilian "labour conscripts" alive.
For a background on this in depth, please see http://www.fischer-tropsch.org and search for "British Intelligence Objectives Committee policy statement."
Also, the author of the site at University of Texas which is the repository for these war records wrote a nice programme summary which was awfully open about the intertwining of US and Nazi business relations throughout and before the war.
As an example, I've a memorandum facsimile from 1940 of the US Bureau of Mines visiting the 38 camps where IG Farben and their affiliate firms had fuel synthesis plants to ensure Standard Oil's and Federally owned patents were not being violated.
I'm sure they saw the slave labour camps up close, and their inmates.
My uncles Jack, Bill and David said they knew they were near a concentration camp by the smell from miles away.
The best proof of the link between fascism and communism is that both Adolf and Joe Lenin had the same boss in their early years.
The Russians made off with the German General Staff records for WW I, but you can see both their paybooks in whatever Russian museum they display these things.
Lenin's "Finland Station" romp-and-run and his stay in Switzerland was paid for by Ludendorff, and so were Hitler's counterintelligence activities as a Freikorps member (where he met Alois Drexler, who is the actual author of Mein Kampf) from 1919 to the mid-Twenties, when he got in thick with industrialists through the Thule Society.
I highly recommend Ian Kershaw's biography of Hitler and "The Story of C," a biography of Sir Stewart Menzies, for all the grisly details. Lenin and Hitler were de facto co-workers.
I also would like to point out something else quite obvious, that had not that giant tick Red China the big, sweaty, and juicy Clydesdales of the Western economies upon which to gorge itself, there would be no Red Chinese Communism whatsoever.
When they drain us dry, that country will go berserk through once again achieving their normal state of being, totally broke, again.
"Trading With The Enemy" by Charles Higham is also an accurate and document-substantiated record of US industrial and Nazi economic complicity.
US industry did then what they have done in response to the Obama election: when they saw a parlour pinko regime coming on board, they jumped ship for the most draconic economic regime they could find on the weight of that regime's promises which, like Hitler's, will ultimately prove empty.
If you think Communist China won't one day laugh and give us the finger (or two) one day, I've some Florida swampland to sell you.
Once a totalitarian criminal regime, always a totalitarian criminal regime.
GE now has forty coal gasification rigs at a cost of 2 billion each in Red China half already built and the other half under construction, yet I know of only 3 in the USA of new vintage being built by them in the USA. That's corporate patriotism for you.