We should expect Mr Duncan Smith to go out and campaign volubly for Brexit in a way about which he felt restrained hitherto. Other ministers may follow his lead. Some may come to regard, as he has done, the whole construct of a Conservative Government led by a clique that is not really conservative, and which is increasingly out of touch with opinion at the grassroots about Europe and a whole range of other questions, as unsustainable: and they will resign too. Mr Cameron says he is “puzzled” by what Mr Duncan Smith has done: if that is a true statement, then the Prime Minister proves his detachment not merely from his core supporters, but from some of his colleagues.