"But there are also unknown unknowns – the ones we don't know we don't know." SecDef Donald Rumsfeld
I don't get why he is laughed at because of that quote. I personally find it quite elegant.
The quote wasn't spoken eloquently but it was profound. He was speaking truth but it was also amazingly ironic. Why risk and assume so much about success in Iraq with the quagmire of obvious unknowns?