Some may find it strange that Prince William apparently decided to end his relationship with Kate Middleton after a meeting attended by his father and his grandparents. In a sense, though, any such gathering would have been not only constitutionally proper but a legal necessity.

Since the Royal Marriages Act 1772, the monarch of the day has had the right to veto the marriage plans of other members of the Royal Family (if they are under the age of 25, which William still is) or to refer them to the Privy Council and ultimately Parliament (if the person involved is older).

Not that this has made for smoother royal relationships. For most of the past 250 years, the rules of the game in royal romances (at least for princes) has been (1) start off with actresses, (2) marry foreigners.