Party politics makes you stupid

This role reversal is a case study in the awesome power of the partisan mindset. Up to a point, American politics reflects abiding philosophical divisions. But people who follow politics closely — whether voters, activists or pundits — are often partisans first and ideologues second. Instead of assessing every policy on the merits, we tend to reverse-engineer the arguments required to justify whatever our own side happens to be doing. Our ideological convictions may be real enough, but our deepest conviction is often that the other guys can’t be trusted.

How potent is the psychology of partisanship? Potent enough to influence not only policy views, but our perception of broader realities as well. A majority of Democrats spent the late 1980s convinced that inflation had risen under Ronald Reagan, when it had really dropped precipitously. In 1996, a majority of Republicans claimed that the deficit had increased under Bill Clinton, when it had steadily shrunk instead. Late in the Bush presidency, Republicans were twice as likely as similarly situated Democrats to tell pollsters that the economy was performing well. In every case, the external facts mattered less than how the person being polled felt about the party in power.