European cities are a mix of unplanned and thoroughly planned. High Middle Ages in more developed places already had some municipal bureaucracy and planning offices.

Take a look at Prague, for example. [0]

There is a chaotic maze of medieval streets in the Old Town (around the Astronomical Clock). But the New Town to the southeast, which was founded in 1348, is already much more regular; the king who founded it had a certain vision and the street grid reflects that vision. Interestingly, a mid 14-th century grid was able to accomodate some degree of car traffic of our modern era.

In case of Kraków [1], there isn't any unplanned corner of the city left, the grid in the Old Town is perfectly regular. This was designed around 1260, so a pretty old grid, but a planned city nonetheless.

[0] https://goo.gl/maps/1cz13fsr5tPP52AF9

[1] https://goo.gl/maps/CRkLPM9i7MRVH1aK8

Many cities are planned. Paris was planned in the 19th century, after it had been around for millenia, and they tore stuff down and rebuilt it.

It's telling that there are people who have never experienced the result of proper town planning and conclude that town planning is an impossibility.

How so? My argument is the "initial planning" of many European cities never really happened. Plenty of planning has happened since, I'm sure!

Remove "initial" from my original post and my point still stands; Europe planned for them at some point, the US didn't, and what the US did - to this article's point - doesn't lend itself to adapt to these parklets so readily.

Yes, in the '80s, '90s, and so on, after _decades_ of very car-centric planning.

The US needs to change how it does planning and learn from the experiences of other countries that actually took steps to become less car-centric.

More likely they inadvertently ‘planned’ for them by planning wide sidewalks that could be then be partially repurposed.

Pre-car cities.