Europe isn't a single state. You cannot generalize all of Europe based on whatever random country your dad or grandparents came from in Europe. If they came from Russia, Germany or Italy in the 30s that would have been very different from comming from say Switzerland or Sweden.

And feudalism died out in most of Europe back in late medieval period.

After Ireland, no country in Europe sent as large portion of its population to the US as Norway, and that wasn't because Norway was not free. In fact it was likely more free than the US in many respects. E.g. when Norway established democracy only about 3% of Americans were eligable to vote. In Norway we let 40% vote, which meant most of the male population.

So why did Norwegian go to the US? Because the US was writing out the largest welfare checks in history with the Homestead Acts. They were giving away land for free to immigrant.

Less than 3% of Norwegian land is capable of growing food, and that land is mostly crap, thin top soil full of rocks, as far North as Alaska. Meaning short growing seasons. In the US in contrast about half the land is farmed. They gave away farm land 3x larger than an average farm in Norway today.

3x the land, with much better soil and climate. That was like winning the jackpot. Of course people came flooding to the US. No other country on the planet gave Joe Average such a large government handout.

It always keeps surprising me how Americans never seem to mention this aspect when discusing immigration. They all seem to have learned this myth about everybody coming to America to just get freedom. No people come due to the handouts, and much higher salaries.

The US has larger landmass than Europe and more farmland, with a fraction of the population when immigrants began arrving in numbers. That gave a huge amount of opportunities.

I wasn't actually suggesting that Americans don't care about their family or community. I made have used bad wording. In fact I think much the opposite. Americans seem to care more about family and community than we do. I experienced a lot of hospitality when I visisted the US.

It is more about mindset. Americans emphasize the individual and their choices and actions. We will think more in terms of structures of society and group dynamics. E.g. I notice when discusing various social issues with Americans, they will criticize people for being this way or that way. They emphasize the outcome as being cause by individual choices. We tend to criticize the system more and individuals less. Not saying there is a right or wrong, just that one thinks about stuff different.

You can read the same if you compare Asian society and American society. There was a famous experiment where American and Asians kids were asked to describe a water tank. Amerian kids would focus on the biggest and more actives fishes and what they did. The Asian kids described the tank more in terms of interactions rather than about any individual in the tank.