If he can't absorb enough as required by the passage of time. He will be gone.
Remember, governors don't know much about foreign relations either...nor do senators or vice presidents.
Except for the muslim world, what do you think Obama knew about foreign relations?
As for Trump....he's defiantly a “risk” as I see it. I prefer Cruz who has a long standing history easy to support from what is significant to me. He's fought a long time for conservatism and against the established quo in Washington and often pretty much alone.
So I prefer less risk when the country is so dangerously close to the precipice....additionally there is just sooo much Trump isn't aware of especially in the halls of Washington...a beast all it's own..... It'll be a minefield for him... and I don't think the country has the 'time' while he attempts graduating from his new rookie status as a political figure to wade through that terrain of the big league games already in play.......he will have to be "led" as through a swampland filled with alligators and snakes.
I just don't think we have 'the time' for a rookie when there is an alternative who knows well the entire domain and it's beasts hiding behind closed doors.