There’s a reason host Jon Stewart has the ergonomic Aeron flight seat and the guests have an ordinary office chair: he doesn’t want his targets to get too comfortable.

Senator Chuck Hagel of Nebraska looked crisp and composed when he showed up to plug his book, “America: Our Next Chapter.” He did get a couple of uncharacteristically humorous zingers in while Jon wasn’t looking, but as entertainment, he had the misfortune to be a Republican who agrees with Jon on the folly of the Iraq war, so the sharpness of comic arrows that typically fly back and forth during a Daily Show conservative target was blunted by Jon’s eager nodding at his anti-war opinions. Without the sparring, the interview just fell flat.

Opinions were also at the heart of Sen. Hagel’s biggest problem on the show: he voiced a lot of them without interesting stories or new perspectives to back them up. Then there was his misreading of the audience for The Daily Show. Anyone interested in the ideas in his book would recognize the appeal right away. But this is a comedy show and the audience who shows up for the laughs, so viewers need to be seduced by the trademark humorous interplay, of which there was sadly little.

Two Whispers and two cardinal Guest Whisperer rules: have a pocketful of short, unexpected stories to hook listeners and viewers into your cause; and know the audience you’re facing and how to engage them.