Optimism born out of nationalism and based on theories of exceptionalism, moderated by “positive” thinking—Americans often confuse this with happiness.
Yet in general happiness scales/studies and ones that also factor in health, environmental stability and the possibility of upward mobility, America fares so poorly. Couple this with more anti-depressant use than any other country and the picture is bleak.
There is also the pervasive cultural norm of performing happiness. Pretending to be happy (usually to make someone else “jealous” or to avoid critical thinking) or being happy only if someone else fails is not happiness. Rejecting critical thinking and calling that happiness is not happiness.
Basking in social privileges (White privilege, male privilege, heterosexual privilege, able-bodied privilege, theist privilege etc) or pretending that they don’t exist while watching others suffer is a form of ignorance and doesn’t measure up to happiness.
Barbara Ehrenreich, from her book Bright-Sided - How Positive Thinking Is Undermining America:
Happiness, after all, is generally measured as reported satisfaction with one’s life—a state of mind perhaps more accessible to those who are affluent, who conform to social norms, who suppress judgment in the service of faith, and who are not overly bothered by societal injustice.