Earlier quoted context omitted.
The nom de guerre Pol Pot didn't appear in the New York Times until August 1976, which was after things calmed down in Cambodia. Which makes your assertion he was doing so at the time unlikely. Vietnam invaded Cambodia and the US began arming Pol Pot and the Khmer Rouge in the late 1970s and 1980s, which again the Times covered, although slightly obliquely. Chomsky condemned the US arming Pol Pot and the Khmer Rouge.
Buzz off with your revisionism. Chomsky said the numerous reports of mass murder were a sea of lies. History has proven him dead wrong. He should have known better but was blinded by his ideology; all too eager to believe America was making it all up, and all too eager to believe leftists wouldn't commit such crimes.
Now you might say "surely he has come to his senses", except Chomsky went on to spread lies about the Sarin gas attacks in Syria.
There's probably more.