Matthew Yglesias argues that the coming royal wedding in England is a good example of the need of the benefit of a constitutional monarchy. Basically, all of the identity politics and the ‘would you drink a beer with that guy’ personality tests get transferred to the royal family, and the politicians can go about the business of running the country.
We follow the royal family with fascination, they participate in weird ceremonies, they have dignity, they symbolize the nation, we all talk about them respectfully, etc. Meanwhile, the Prime Minister gets to be just another politician.
We need a king.