Why Do We Have “Sister Cities”?

Perhaps I missed it, but the article does not seem to mention the obvious personal incentive for public officials: an exchange of free vacations. That seems naive.

I'm curious if this idea has been explored in large organizations as a way of building understanding (read: breaking silos) between various departments/groups/teams.

How does priceonomics keep cranking out these articles while maintaining an otherwise boring product? Its impressive and simultaneously confusing.

The rationale of "Peace" seems a little weak to explain why there are so many sister cities between France and the UK, since there has been no direct conflict between the two countries for a long while now - and certainly it would not explain why the number has increased after WWII where France and the UK were clear allies (the UK even hosting Degaulle's call to resist).

Between westeners at worst no more than curiosities, but they are a good platform to start business in the East, where previous contacts and trust building is more important.