McNamara is the one I obsess over. Combined with Johnson, the two of them are probably responsible for at least... well, a lot of the men we lost.
The war should have been fought to win. We should have devastated the north in short order. We played patti-cake instead.
Nixon had the right idea with bombing the north. He could have finally won the thing if Congress had quite interfering.
May I suggest
Dereliction of Duty by H.R. McMaster.
It was a cathartic read. After every twenty pages, I would swear, throw the book against a wall...and spend a half-hour walking around the block...walking off my rage.
But, in the end, I ended up understanding what really happened...and who was responsible. And, mostly, it was Johnson and MacNamara...aided and abetted by a host of arrogant academics who were totally ignorant of reality.