Something's not right. I'm sitting in The New Yorker's headquarters opposite Hendrik Hertzberg, the finest political commentator in the Conde Nast skyscraper, and my mind loops back to high school political studies. Our interview hasn't properly begun, and already he's riding his wonkish hobby horse of electoral systems.
In Politics: Observations & Arguments, his 2004 compendium of journalism spanning nearly four decades, he makes the case for 'mixed-member proportional voting' as a template for US electoral reform.
During his four years in the White House, as a member of president Jimmy Carter's speechwriting team, Hertzberg became convinced many of America's ailments stemmed from its single-member electoral districts, which prevent popular majorities being reflected in policy. 'Probably only 10 per cent or 15 per cent of congressional seats are competitive,' says the relaxed 66-year-old. 'But with a proportional system, you can have nationwide political mobilisation.'
Worthy talk, for sure. But as his disquisition on world voting structures clocks 10 minutes, it has grown as intricate and winding as a Californian gerrymander and shows no sign of letting up. Hertzberg, though, is so amicable, so obviously enjoying himself, it feels churlish to interrupt.
As The New Yorker's main writer of the weekly Comment essay, Hertzberg has a voice that stands out for its warmth and common sense. Novelist Philip Roth has praised its 'uncommon journalistic modesty', at odds with the shrill bellicosity typical of the commentariat.
He's a bleeding-heart liberal but also a master of takedowns, drawing blood from the cruel hard-right. After Hertzberg charged former House Speaker Newt Gingrich with homophobic bigotry, Fox News host Bill O'Reilly dispatched reporters to ambush Hertzberg on his way to work, then on his nightly news programme aired the full exchange with the bemused and pre-caffeinated writer.