Former Massachusetts governor Mitt Romney will speak at the University of Michigan on May 12, 2011. (Photo by Win McNamee/Getty Images) (Win McNamee/GETTY IMAGES)

The difference? Romney will not be addressing personal relationships or personal decisions, as Obama did in response to criticism over his affiliation with the Reverend Jeremiah Wright, or as Clinton did amid charges of extramarital affairs and draft dodging. Instead, Romney will be trying to turn the page on a major achievement of his tenure as governor, the Massachusetts plan that served as a model for the federal health-care law that’s now reviled by conservatives.

If that sounds odd, it is. The health-care plan in Massachusetts may have had mixed success—many more people have coverage, though there have been some higher costs—but at least in the eyes of Bay State citizens, it wins generous applause. Some 84 percent of the state’s residents say they are satisfied with the program, according to a poll released in March.

That means that rather than trying to explain questionable relationships or decisions of his youth, Romney will be trying to defend what’s arguably the greatest achievement of his governorship. His aides have told reporters that the speech will try to shift the narrative away from the plan in Massachusetts, and how similar it is or isn’t to the federal law, toward a more forward-looking discussion on how he plans to repeal Obama’s plan and replace it with his own. While he reportedly won’t renounce the Massachusetts law or his role in it, he apparently doesn’t plan to speak much about the past, either.

If that’s the case, I doubt the speech will be so pivotal after all. While Romney is to be commended for trying to shape the debate—one of the first rules of communication for leaders—he’ll never change the narrative himself unless he first addresses the issue head on. He could give an apology, which may be the only way to make some conservatives happy. He could offer up a full-throated defense, separating himself from the pack and standing up for his past achievements. Or he could provide a coherent explanation for why it worked in Massachusetts but may not work in other states—the most likely outcome given Romney’s repeated statement that such reforms should be left to the states.

But as long as he remains trapped on middle ground, his attempts to spin the discussion forward without addressing the past head on are likely to go nowhere. This is not a speech to address a character flaw or a questionable relationship that can be explained away with lofty rhetoric or folksy charm. Rather, it’s a complex issue of national urgency that sits right at the heart of conservative fury over Obama’s first term. Unless Romney is able to directly square his candidacy with his past policies—something that won’t be easy to do—Thursday’s “defining” speech may indeed be pivotal, but in the wrong direction.

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