In the 1990s, after well-lubricated lunches with her former aides Charles Powell and Bernard Ingham, Margaret Thatcher would sometimes declare: “Come on, we are going to march up Downing Street and reclaim No 10.”
Few prime ministers have so yearned to return to government after being evicted (Powell believed that she never had another happy day). But holding office – as Thatcher’s successor John Major learned – is not the same as holding power. The struggle for intellectual and political supremacy is waged over decades, not years. Truly great leaders govern in exile by forcing their successors to retain their reforms.