Meaning: I would never do such a thing. I would never cross such a boundary.
Examples:
I would not be a policeman or a soldier for all the tea in China. It is against my principles.
I would not have an affair with him for all the tea in China.
Meaning: Examples:
Wild horses would not drag him to the psychologist (ie, it will be very difficult or impossible to convince him) because he thinks that it is a waste of time and money.
Wild horses could not drag me to that mausoleum because it symbolises the Franco regime. (= No way will I go there.) I think it ought to be demolished.
