I’ve been thinking about this all night: Eric Fehrnstrom’s Etch A Sketch gaffe yesterday may go well beyond a momentary embarrassment and become a campaign-defining disaster, much as John Kerry’s “I voted for it before I voted against it” gaffe — which came at almost exactly the same point in that campaign, as Kerry locked down the nomination — was in 2004. This is true for several reasons:

1. Most obviously, this was a classic Kinsleyan gaffe — an inadvertent blurting of the truth — that goes to the very heart of the character problems that have bedeviled Mitt Romney throughout this campaign. It provides a handy prop for Romney’s opponents and an obvious template for future TV ads.

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2. It makes it much harder, perhaps impossible, for Romney to begin to tack back to the center to appeal to centrist voters, an absolute necessity for the fall campaign after the free-range extremism of the Republican primary. Every time Romney makes a move or even a head fake, it becomes an Etch A Sketch moment.

3. There is a gestalt to every campaign, a deep organic spirit. Kerry’s campaign was infected by the candidate’s indecision about what to do regarding the war in Iraq. Bill Clinton’s campaign was propelled by his native resilience. George W. Bush succeeded because of his gormless certitude. The Obama campaign’s steadiness emanated from the candidate’s no-drama persona. In Romney’s case, this spirit expresses itself in embarrassing gaffes, often at the moment of victory — and it reflects the sterile management-consultancy ethos at the heart of the candidate. In last week’s issue of the New Yorker, Louis Menand had a terrific essay about how this ethos really is Romney’s defining characteristic. A management consultant or private equity turnaround specialist can wipe the slate — or Etch A Sketch — clean and start anew with each new project. A political candidate can’t. There has to be some passion for a presidential candidacy to work. Romney has none, just a deep abiding faith in his ability as a turnaround guy. A turnaround guy. A turnaround guy.

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