I can't speak to every European country, but Portugal also has a lot fewer stop signs and traffic lights than the US (roundabouts are one reason, but there are

I can't speak to every European country, but Portugal also has a lot fewer stop signs and traffic lights than the US (roundabouts are one reason, but there are multiple four-way intersections on my street that would have stop signs in the US). Given the way American streets are set up, rigorously enforcing stop signs is probably beneficial, but I think other factors about how streets are arranged and how people drive are more important.