Robert MacNamara - the US Def Sec who in 1967 recommended freezing troop levels, stop the bombing of North Vietnam and for the US to hand over ground fighting to South Vietnam. Rejected outright by President Lyndon B. Johnson (who was an @-hole IMHO). McNamara's recommendations amounted to his saying that the strategy of the United States in Vietnam which had been pursued to date had failed (which was correct). Nearly 40,000 US servicemen died after this date!
Was he so wrong? I don't think so. Plus he had the dignity to fall on his sword when no one would listen to him!
He also ran 2 successful ventures - The Ford Motor Company (and opposed the dreadful Edzel) before he became Sec Def and also the World Bank until the 80s.
I just don't see him as your model for disaster.
LJ
