It's taboo to point this out, especially on HN, but I'm feeling bold today:
You can't discuss the socialist policies of Western European countries without addressing their wealth. And you can't discuss the current wealth of Western European countries without acknowledging the process by which they acquired that wealth.
The "nice socialism that Sanders has been raving about" is the kind that is practiced in countries with a long history of colonization and slavery[0]. During this timeframe, they "earned" a massive amount of money by extracting resources from people that they literally enslaved. This started before the 17th century and continued into the 20th century.
Those people who were colonized and enslaved (and their countries) are still feeling the effects of that today, and they would not be so quick to describe that kind of socialism as "nice".
[0] Denmark and Sweden are the two that Sanders has called out specifically by name.