I see the common thread in the top 20 Countries for happiness:

Rank Country

1 Norway

2 Denmark

3 Iceland

4 Switzerland

5 Finland

6 Netherlands

7 Canada

8 New Zealand

9 Australia

10 Sweden

11 Israel

12 Costa Rica

13 Austria

14 United States

15 Ireland

16 Germany

17 Belgium

18 Luxembourg

19 United Kingdom

20 Chile

They are all Capitalist Democracies: there is not a truly Socialist Country on the list. Although several of them have elected Governments that describe themselves as Socialist (mainly Scandinavian welfare States propped up by North Sea oil), none of them have Government controlling the means of production, all have private businesses and all protect private property.