>> the president's logic at the time look, it's been a decade. we can't stay forever. the united states, you know, can't hold a country together. iraq has to be ready to have democracy and stand on its own. ultimately wasn't that a decision that had to be made? trillions of dollars had been spent. it was continual, hundreds of billions of dollars a year, and things weren't getting better. >> you know, i sat in on the margins of the national security meetings when george bush was president. and he used to say iraq and the future needs to look like south korea. if you look at south korea today, it's a vibrant economy, but u.s. forces are still there 60-plus years after the end of the korean war. that's what he was talking about. and if u.s. forces were in iraq in substantial numbers today, 15,000 or so, we wouldn't have isis in control of a third of the country. >> you think that would have been enough, 15,000? >> i think so, 15 to 20,000 would have been sufficient numbers to have combat capability, advisers to the iraqi security forces, intelligence operators.