Unemployment in northern Europe is lower than in comparable places in the US with the same labour rights.
I can imagine unemployment in Southern Europe to be higher, but I am curious what you think you are comparing.
Here is something else to think about: it's safer to hire Americans because they will work 60 hours a week, never take a sick day, won't get pregnant and even if you give them vacation days they won't use them. So they are about 3/5 of the price of your typical European employee. A much better value proposition.
In return some of this will burn them out and put them on edge. This will likely have cultural, political and social consequences. If only we could give our American friends the sleep, reflection and family time they so much deserve.