King Willem-Alexander of Holland and his wife Queen Maxima welcomed Barack Obama and other world leaders to the royal palace in The Hague on Tuesday.

They were gathered for a Nuclear Security Summit.

The King and Queen of Holland became monarchs after Willem-Alexander's mother, Queen Beatrix, abdicated in April last year.

The summit included an interactive nuclear war game in which each of the world leaders were invited to test their responses to a terrorist atomic "dirty bomb" attacks that threatened the lives of hundreds of thousands of people.

According to a report in The Telegraph, "Angela Merkel, the German Chancellor, was less than happy at being asked to play games around the table but her complaints were overruled because Mr Obama backed the idea and was keen on playing."

Yes, here in Old Europe, we know our place.