When the networks (flouting the debate rules) cut to Mr. Bush while Senator John Kerry was speaking, the president had the hunched shoulders and the peevish, defensive look of an incumbent under heavy attack.

And it was body language as much as rhetoric and one-liners that distinguished the two candidates in last night’s debate. The networks were right to disregard the campaigns’ ban on cutaways and reaction shots. Instead, all the networks, including Fox News, lavished viewers with split screens and shots of the candidates from almost every angle, including shots from behind the president’s tensely knotted back.

Television homes in on feelings hidden beneath rehearsed words and reveals instinctive responses and glimmers of personality.

The cameras demonstrated that Mr. Bush cannot hear criticism without frowning, blinking and squirming (he even sighed once). They showed that Mr. Kerry can control his anger and stay cool but that he cannot suppress his inner overeager A student, flashing a bleach-white smile and nodding hungrily at each question.
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The decision to have the two lecterns be of matching height (50 inches) turned out to work against Mr. Bush. The agreed-upon lectern cut the president mid-chest, and made him look smaller, as if he were in a bunker. He did not extend himself beyond its confines, but instead kept his arms in front of him, barely peeking above the lip of the lectern.
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At the end of the debate, the candidates’ wives had their own moment of nonverbal oneupmanship. Both wore white silk suits, and both tried to be gracious. Laura Bush smiled and whispered something in Teresa Heinz Kerry’s ear; Mrs. Heinz Kerry turned their hug into a jaunty joint wave to the crowd. Mr. Kerry got into the shot with the two women. Mr. Bush went to his daughters in the corner and rushed offstage.