>>I wonder if the root cause for all of this is poor instruction on stress management and anger management.

Do citizens of countries with low stress and anger levels receive such instructions?

Because if not, lack of such instructions is unlikely to be the "root cause" of the observed phenomenon.

Instruction on stress management and anger management is driven by parenting and school environments, not by state-mandated education and mandatory stress management workshops.

If you see your parents constantly on the verge of bankruptcy and lay-offs, struggling to pay off medical bills and resorting to shouting as a stress relief mechanism, then odds are, you'll grow up thinking this is the norm.

Cultural values and government policy are symbiotic.

I think it's culturally and socially driven. As an outsider looking in I have discussed American capitalism with others and its more ruthless nature compared to the more moderate varieties of Europe. The US GDP (ppp) per capita is very high for the size of it's population (and not being a tax haven or major oil exporter). Even compared to a wealthy powerhouse like Germany the US has a gdp per capita $10k higher. I don't believe that is due to the Us being a more efficient economy. It's because US employees and citizens aren't afforded the same services, rights, and level of care that people in countries like Germany do get that alleviates the stresses of daily life.