(I used to live in a neighborhood full of them and I liked them but very many people disagreed with me. If you make speed bumps not work then they will all be replaced with slaloms or circles.
Is there any serious argument against them? I've heard they aren't common in America.
They were rare in the US before, I want to say, 15 or 20 years ago but I see them all the time now and new ones are always being installed. Good traffic devices, with the above tradeoffs in mind.
Where roundabouts get bad is when they’re multi-lane and can get a lot of traffic. There’s one I se fairly regularly and I’m surprised there aren’t more accidents.
Regarding pedestrian safety that seems like it should be easily solved by those flashing lights that they can trigger with a button. Or some other signal based solution.
As a result, I hated them until years later, when I encountered one that was done correctly. After that, I completely flipped my opinion. Done right, they can completely beat a traffic light for wait time and throughput.
They are in the Northeast. But they don't always keep bad drivers away.
For America specifically: they're not a great fit for places where everything is spread out and the road system is sensibly designed. I can drive from one side of Tulsa to the other (on streets, not freeways) in a fraction of the time I could drive across a similarly-sized European city. That's because the city itself is designed for cars. It has straight major streets with 40-45 mph speed limits that form a grid. Neighborhoods sit inside the grid and the streets in them curve with the landscape. In most of the city you have maybe 3-5 traffic lights per mile on the major streets, so unless it's rush hour you get minimal slowdowns. Sometimes I can drive several miles without hitting a red light.
The ideal situation is to have a straight road with no traffic directly between you and where you want to go. Obviously, that's not possible. So you have to compromise. Roundabouts suck, but they're better than almost any other option in places that have twisty narrow streets and lots of pedestrians. Many (most?) American cities aren't like that (at least to the extent European cities are), so roundabouts don't make as much sense here.
They're getting more popular in the Puget Sound area. We have been re-engineering streets to include roundabouts all over the place. I think they're a great thing, but too many people still stop at the wrong time.
Are there traffic circles that are primarily about slowing traffic rather than managing intersections?
https://www.washingtoncountymn.gov/DocumentCenter/View/2296/...
IRL this is probably just handles small bumps and turns comfortably thing.