How did it happen that an accusation once confined to the lowest, whiskey-soaked level of politics or rank propaganda campaigns is occurring daily in American politics?

No one has worked harder to revive this low-rent tactic than New York Times columnist Paul Krugman. To my knowledge, Mr. Krugman is the only columnist writing for a major publication in U.S. journalism who has so routinely and repetitively accused people of being liars.

It began with the charge that Bush lied about WMD and became almost banal in its repetition after that. In a September 2008 piece on the GOP convention, “Blizzard of Lies,” the New York Times’ heir to Reston, Wicker, Krock and Safire blew the floodgates: “they’re all out-and-out lies”; “the blizzard of lies”; “a grotesque lie” and “the McCain campaign’s lies.” The Obama campaign is saying “Romney lied,” because Paul Krugman made it the coin of their realm.

The L-word’s strength is directly proportional to the rarity and appropriateness of its use. Today in our politics it is as skuzzily routine as the F-bomb has become among 15-year-old girls on the New York City subways. This is not progress.