Why politicians are always accusing each other of lacking seriousness.

House Republicans aren't the only ones gambling that the public is serious. Seriousness is also a fixation on the campaign trail. In discussions with advisers or supporters of three prominent campaigns, each has invoked the seriousness of the American people in exactly the same way. Newt Gingrich will be able to overcome his corrugated marital history because voters are so somber. Republican voters will overlook the similarities between the health care plan Mitt Romney promoted as Massachusetts governor and the one Obama pushed because they are so serious about the economy, an issue on which Romney claims special expertise. Haley Barbour may be a former lobbyist with a thick Southern accent, but voters won't care because, as an influential Republican lawmaker explained to me recently, "voters are in a serious mood."

They may well be. But when politicians invoke seriousness like this, they are using it as a diversion. When a candidate has no easy way to overcome an obstacle to his campaign, he will seek to diminish it by pointing to something else. This is a time-honored technique, though its most notable recent use has been by Democratic presidential candidates in 2000 and 2004. Both Al Gore's and John Kerry's campaigns argued that Americans would overlook their shortcomings because they wanted a "serious" candidate. This theory also requires that people see President Obama as unserious. Cool, detached, and cerebral, maybe. But one ill-timed televised discussion of his NCAA bracket isn't likely to make voters take seriously the idea that he's not, well, serious.

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