I have written on this subject before in comments on the book “Gross National Happiness” by Arthur Brooks (here) and in relation to some quick-and-dirty research I have undertaken myself.
To recap briefly, survey data show that Americans who label themselves as conservatives are nearly twice as likely to say they are very happy as are those who label themselves as liberals. This gap has persisted for 35 years and apparently cannot be explained in terms of income differences. Religion and marriage account for some but not all of this happiness gap. My research suggests that the finding that conservatives are happier than liberals also applies to other countries: a higher proportion of the population are satisfied with life in countries where people tend to position themselves toward the right of the political scale (here). It also suggests that differences between the happiness of high and low income people is influenced by differences in their political beliefs and in their beliefs about the importance of money and material things (here).
An article by Jaime Napier and John Jost (kindly brought to my attention by Andrew Norton) seems to me to shed light on the reasons why political beliefs influence happiness (‘Why are conservatives happier than liberals?’, Psychological Science, 19 (6), 2008). The study suggests that some of the association between political orientation and subjective well-being is accounted for by beliefs about inequality. The authors examined the effect of introducing ideological variables - relating to beliefs about inequality and meritocracy- in regression analyses explaining life satisfaction in the U.S. and nine other countries. They found that when the ideological variable was introduced into the analysis it took some of the explanatory power away from the political variable. The authors also report on a study which suggests that the gap in happiness between conservatives and liberals in the U.S. tends to become wider when the degree of income inequality rises.
The authors conclude that “inequality takes a greater psychological toll on liberals than on conservatives, apparently because liberals lack ideological rationalizations that would help them frame inequality in a positive (or at least neutral) light”. What they presumably mean is that people who label themselves as conservatives are less likely to worry about income inequality and this partly explains why they are happier than those who label themselves as liberals.
What are the implications of the finding that beliefs about income inequality influence happiness levels? It seems to me that when concerns about inequality are apparently having an adverse effect on happiness of large numbers of people we need more research to know more precisely what these people are concerned about and whether their concerns have a factual basis.