This is a wonderful article.

Not being American and not having lived through the Vietnam war (nor am I a history buff) I wasn't particularly familiar with McNamara, but I watched "the fog of war" years ago, and it's a brilliant movie.

What stayed with me was that McNamara states that their reasoning for getting into the war was (partially) based on incorrect understanding of the situation (i.e. that Vietnam would side with China).

This squares with the persona described in the article, and with the idea that having a lot of information is fundamental but maybe not enough if you don't have the right bits.

Something to keep on mind.