Look: I really don't give a s[inks]t about foreign policy or whether a candidate knows much about it, and we all know that the President of the United States is going to have more foreign policy advisers than literally anyone else in the world upon swearing in, but he really needs to have at least a fundamental set of talking points that jives with conventional military thought on the matter. Otherwise, he will continue to look like a bumbling old fool and it will negate his debate strengths in other categories among anyone not already firmly in his corner.
This is so irresponsible. Virtually any complicated job requires good intuition and rock-solid fundamentals to make good decisions, no matter how much advice one is given. Just like you can't just read a book about skiing and then go out there and ski, even if you're surrounded by ski instructors. You have to have a feel for what the right thing to do is.
It's a lot more than just weighing pros and cons and using common sense. If that was all there was to it, the president wouldn't have to make decisions because his advisors would make them for him and tell him exactly what to do. They trust the president to synthesize their advice with his or her judgment, experience and intuition to make the right decision.