Indiana Gov. Mitch Daniels (R) gave a perfectly serviceable speech last night. It was a bit dull, maybe, but it wasn’t a wrenching exercise in self-humiliation. Which is to say, by the standards of post-SOTU responses, it was a stunning, historic success. But it was also a reminder of the difficulties Daniels, a fantasy-draft presidential pick for many Republicans, would face if he entered the campaign.

Indiana Gov. Mitch Daniels (R) speaks during a news conference on the signing of an education bill dealing with required annual teacher evaluations in his office Indianapolis, April 30, 2011. (AJ Mast/AP)

What Daniels didn’t say is that he, Mitch Daniels, held a command post during many of these mistakes.

Daniels was George W. Bush’s first budget director. He served from 2001 to mid-2003. That is to say, he oversaw the first round of tax cuts, and the initial cost estimates of the war in Iraq, and the development of the deficit-financed Medicare Prescription Drug Benefit. During his time as Bush’s budget director, the deficit increased by almost $200 billion. After he left, the policies he helped pass would add trillions more to the deficit. They are still adding to the deficit today.

These policies cannot all be laid at Daniels’ feet. It is unlikely that Bush’s budget director was heavily involved in the decision to enter Iraq -- though Daniels did produce short-term cost estimates that helped reassure Congress, quite wrongly, that the war would be swift and affordable. But the same cannot be said for the Medicare expansion, or the tax cuts. And as the New York Times has pointed out, these policies, together, have done more damage to the deficit than any legislation signed into law under President Obama.

Perhaps this wouldn’t matter if George W. Bush was revered by Republicans. But he isn’t. Bush left office one of the most unpopular presidents of all time. Under his watch, deficits soared despite an economic expansion. Under his watch, we suffered the worst financial crisis since the Great Depression, and the oceans of red ink that we face today are just one of its many aftereffects. The Tea Party was, in large part, a reaction to the damage Bush did to the Republican Party. And today, it is common for conservatives to admit that the Bush years were characterized by an inexcusable profligacy, and to swear that such a spectacle will never again repeat itself.

Daniels has not been profligate as governor of Indiana. Quite the opposite, actually. And when compared to Mitt Romney and Newt Gingrich and Rick Perry and Tim Pawlenty, he looks pretty good. But everyone looks pretty good before they enter the campaign. See, for example, Rick Perry and Tim Pawlenty. Indeed, at one time, this field looked good enough that Daniels’ family was able to persuade him not to run — an argument that must, in part, have been based on the belief that he was likely to lose.

If Daniels did enter the campaign, he would cease to be an example of sober Republican governance and immediately become a threat to a field of experienced, well-financed, defensive candidates. They would hang him with the mistakes of the Bush years. There would be endless articles by reporters looking into exactly what role Daniels played in costing out the Iraq War, and selling the tax cuts. There would be investigations into whether it was really proper for Daniels, an Eli Lilly executive through the 90s, to have gone from working at a pharmaceutical giant to working on Medicare Part D for the Bush administration.

And then there are Daniels post-Bush administration heterodoxies. There would be a raft of attacks over Daniels’ 2005 proposal to impose a surtax of one percent on income over $100,000—a proposal that was killed by the Republican Speaker of the House in Indiana, and that would quickly be dubbed “Obamanomics” in the primary. There have already been attacks on Daniels’ efforts to expand Medicaid in Indiana -- a proposal that Cato’s Michael Cannon called “Daniels’ Obamacare problem.”

Daniels would, in sum, face an unusually acute version of a problem that has afflicted almost every other candidate in the Republican race. Over the past decade, the Republican Party has disowned a Republican president and rejected a slew of once-uncontroversial policies. But though the Republican Party can change its positions, Republican politicians can’t change their pasts. This has proven a problem for not only Romney and Gingrich, but also more generic conservatives like Pawlenty and Jon Huntsman. Daniels, who has both been a policy-minded governor and a key figure in the Bush administration, would have a lot to answer for.

Perhaps Daniels could withstand these attacks. Perhaps the Republican establishment would rally around him. Perhaps he would quickly emerge as the frontrunner. But it’s just as possible that Daniels wouldn’t be ready for their ferocity. He wouldn’t be prepared for the rigors of the campaign. He would have an organization capable of protecting him. he would make mistakes. He wouldn’t know every skeleton hiding in his closet, and he wouldn’t be ready for some of the attacks that came his way. Perhaps, in his desperation to make up for lost time, he would attack the frontrunners in a way that would backfire and damage his brand. Soon, he would look like just another in the race’s long line of disappointments.

A year ago, I had hoped Daniels would enter the race. He has been an unusually responsible voice in the Republican policy establishment. Unlike much of his party, which had contented itself with pure opposition, Daniels had proposed plausible deals that Republicans could strike with the Obama administration on health care and stimulus. But the fact that Daniels would have been a worthy addition to the field doesn’t mean he would have had an easy time as a candidate in this field, much less that he could enter, at this late date, without following the pattern of most late-entry candidates and finding himself quickly tossed aside.