Kennedy ranks highly in polls of U.S. presidents with historians and the general public. His personal life has also been the focus of considerable sustained interest, following public revelations in the 1970s of his chronic health ailments and extramarital affairs. In addition to addressing Britain's failure to strengthen its military in the lead-up to World War II, the book also called for an Anglo-American alliance against the rising totalitarian powers. Kennedy became increasingly supportive of U.S. intervention in World War II, and his father's isolationist beliefs resulted in the latter's dismissal as ambassador to the United Kingdom. This created a split between the Kennedy and Roosevelt families.