Ah-huh. I'd be surprised if every single candidate for the Presidency since WW2 hasn't promised this.
The withdrawal of the US as world policeman? Really? Successive Presidents have all emphasised their support for an active foreign policy, normally with some rejoinder that they "don't like to do it, but someone has to" or some nonsense along those lines.
I'll give you that I have serious doubt of his ability to force any change. Unless he has a serious team ready to go to shift the US foreign policy stance quickly he has no nope. They're trying to lock in an aggressive liberal foreign policy setting in Washington at the moment and if the TPP gets signed before he gets there, there's not a huge amount he can do in the Pacific.