Here's the Genghis Khan quote, made by Kerry in 1971, as reported by the Washington Times (May 2, 2004):
"He [Kerry] asserted our soldiers 'raped, cut off ears, cut off heads,... cut off limbs, randomly shot at civilians, razed villages... reminiscent of Genghis Khan, shot cattle and dogs for fun, poisoned food stocks, and generally ravaged the countryside.'"
The movie depicts rape (of a Vietnamese girl by American soldiers), razing villages, shooting for fun, etc. It also compares what the Americans were doing to the exploits of Genghis Khan.
Hmmm.
Lang could have done an interview that served as a basis for his 1969 article. If he did, who was the subject? Kerry's testimony was in 1971......did he use Lang's article for his testimony? Like you, I say a loud hmmmm in the similarity of the language used.
As you can readily tell, I get lost in details that may not be relevant. :)