America routinely ranks fairly low on the "happiest countries" rankings. Currently #24 behind most of Europe, with the Scandinavian countries typically at the top.
https://worldpopulationreview.com/country-rankings/happiest-...
Clearly other countries are doing something to keep their citizens happy that the US is not copying.
Given that US politics and policy is driven by lobbyists and tribal infighting, would you really expect anything different?