This is shaping up to be the second election in a row that’s about someone who isn’t on the ballot: George W. Bush.

In 2008, Barack Obama won in no small part by turning the election into a referendum on President Bush and by claiming that a John McCain presidency would amount to a third Bush term. Since then, Obama’s presidency has been one long run-on sentence of blaming his predecessor, only occasionally punctuated with complaints about Europe, ATMs, the GOP Congress, Fox News and tsunamis.

Like a general fighting the last war, Obama is going with what’s worked for him in the past. And the thing is, it might work for him in the future.

Whatever character flaws Obama’s relentless buck-passing might reveal, and whether or not it’s fair to Bush, the simple fact is that it may well be good politics. The Obama campaign has spent millions on polls and market research. If Bush-bashing was really hurting Obama’s numbers, he’d stop doing it. Instead, he relentlessly insists in ads and speeches that Mitt Romney represents a return to the Bush years.

“If you agree with the approach I just described, if you want to give the policies of the last decade another try, then you should vote for Mr. Romney,” Obama declared in his June 14 speech in Cleveland.

Romney hasn’t helped matters. When asked by NBC’s Brian Williams to explain how his plan differs from Bush’s policies, Romney offered up familiar talking points that could have come from Bush himself. Now, I agree with those points – exploit domestic energy, promote trade, keep taxes low, etc. And you could easily find banal throwaway lines from Obama that at least make it sound like he does, too.

But Obama has the distinct advantage of being branded as the anti-Bush candidate in the race.

Romney needs to explain to voters why he’s not Bush 2.0. Republican politics have been off-kilter for several years now because a large segment of the conservative base does not look back fondly on the Bush presidency. The mainstream media’s various narratives about the Tea Party ignore a vastly more significant and powerful motivation than the various bigotries and conspiracy theories typically ascribed to them. The Tea Party feels the GOP under Bush’s “compassionate conservatism” gave up the store to big government.

Whether this is fair is an argument for another time. The political reality is that many people believe it. This is why Obama constantly talks about “inheriting” all of this debt from Bush. And that’s true. Obama did inherit a deficit when he came into office. Why this fact justifies racking up vastly more debt and bigger deficits is a logical mystery.

In the last four years we’ve added $6.3 trillion in federal debt, with $5 trillion of it fully on Obama’s watch. In 2008, debt held by the public was 40.5 percent of GDP. It’s now 74.2 percent and growing.

In short, Romney needs to say that when it comes to spending and the growth of government, it’s Obama who’s closer to “Bush on steroids.”

To do so, Romney must challenge Obama’s theories of both the past and the future. The notion that Bush was a government-shrinking market fanatic is bizarre. Under Bush, the federal government spent more than 3 percent of GDP on anti-poverty programs for the first time. Education spending rose 58 percent faster than inflation. Bush gave us Medicare Part D, the biggest expansion in entitlements since the Great Society – until Obamacare. He signed Sarbanes-Oxley, created a whole new Cabinet agency (the Department of Homeland Security), and was the originator of the bailouts, TARP and the first stimulus program.

Obama took many of these policies and approaches and expanded them. Historians will look back on the Bush-Obama years as a time of largely uninterrupted growth in government and debt.

I don’t believe the Republican Party would punish Romney for a policy-heavy “Sister Souljah moment.” I’ve made this argument in front of numerous conservative audiences (and recently in the pages of National Review) with little to no objection. My hunch is that Bush himself would be happy to serve as a punching bag if it would help.

Romney shouldn’t attack Bush personally. Nor should he be strident in his criticisms of Bush policies. (There are substantive defenses of his record to be made.) But Romney is under no obligation to defend runaway spending by either party. Indeed, congressional Republicans admitted that, in the words of Rep. Mike Pence, “we lost our way” during the Bush years. They subsequently won back the House in 2010.

Romney should follow their example.

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