Heidi M. Przybyla

USA TODAY

There may be one complication for Donald Trump in attacking former president Bill Clinton’s record on the economy: Donald Trump.

The real estate billionaire and presumptive Republican presidential nominee fired an opening salvo on Tuesday in response to Hillary Clinton’s plan to put her husband in charge of revitalizing the economy.

“How can Crooked Hillary put her husband in charge of the economy when he was responsible for NAFTA, the worst economic deal in U.S. history?” Trump tweeted.

Yet as recently as last year, Trump called Bill Clinton the best of the past four U.S. presidents. In 2008, Trump called him a “great president” and said the Clintons are “fine people.”

In a June 2015 interview on MSNBC’s Morning Joe, Trump was asked to pick the best of the past four presidents, and he chose Clinton.

“I would really say Clinton, probably,” he said. “Had he not met Monica, had he not met Paula, had he not met various and sundry semi-beautiful women, he would have had a much better deal going,” Trump said.

Most of Trump’s public praise for Bill Clinton came during the late 1990s, as his presidency wound down.

“I think Bill Clinton has done a terrific job. I don't think he's been treated very fairly,” Trump told CNN’s Robert Novak in 1997. Two years later, he described Clinton as someone who "could have gone down as a very good and almost great president, primarily because of the economy," according to the Associated Press.

The battle between Hillary Clinton and Trump in the fall is expected to be the fiercest in the industrial heartland and rural Appalachia, communities where working-class, white voters have been devastated by manufacturing and coal industry job losses.

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To offset Trump’s appeal in these areas, Clinton has in the past few days attempted to put her husband out front, hoping he remains a popular figure in the region. Clinton carried many of these states, including Kentucky and West Virginia, in both his presidential elections.

While Trump has based most of his criticism of the Clintons on character issues, including President Clinton’s treatment of women over the course of his public life, the top concern for most voters is the economy and jobs, and that is where the Clintons will focus.

It may not matter to these voters that Trump was previously complimentary to Bill Clinton, as they’ve proven to be loyal supporters of the real estate mogul in a series of primary states. Further, Hillary Clinton’s March comments about putting the coal industry out of business — which she later apologized for — have proven toxic in these once friendly states.

Yet the Clinton campaign is hoping that Bill Clinton can help if the former president plays a more prominent role on economic policy. And Trump’s previous praise gives him a talking point. On Sunday, the former secretary of State said she'd put Bill Clinton in charge of "revitalizing the economy," and "especially in places like coal country and inner cities and other parts of our country that have really been left out."

The Trump campaign did not immediately respond to USA TODAY's request for comment.

Former Republican congressman Tom Davis said that while NAFTA is a good target, Bill Clinton is not. “I don’t think Trump should engage Bill Clinton. He misses the target. The target is Hillary. If he runs against Bill Clinton, he probably loses,” said Davis.

The former president polls better than his wife in these communities, where “they remember the good years, particularly among Trump’s target voters,” Davis added.

It’s unclear whether Trump’s tweet is the start of a broader effort to tarnish Clinton’s economic legacy or whether it will remain a more narrowly targeted attack on his role in enacting the North American Free Trade Agreement (NAFTA).

Trump made trade deals, including NAFTA, a centerpiece of his bid for the Republican nomination, and he’s already blamed Bill Clinton.

"NAFTA was a Clinton deal and he wanted it so badly, and I have not been a big fan of what went on in terms, economic development, or with the war with Bush either, frankly," Trump said May 9 on CNN. "If you look at NAFTA and look at what's been done and how hard Clinton pushed it, and that bill has been an absolute disaster." The deal was officially signed by George H.W. Bush and enacted through legislation signed by Clinton.

If the critique does broaden,his previous comments will likely garner more attention.

“The Republicans are always more effective in theory, but it doesn't always work out that way,” Trump told Fox News Channel's O’Reilly Factor in 2004. “If you look at Clinton, I mean, we had some great years under Clinton, whether you loved Clinton or didn't like Clinton.”

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He repeatedly heaped praise on Clinton for Treasury Secretary Robert Rubin and Federal Reserve Chairman Alan Greenspan, which he called his “two best appointments,” in 1999 on NBC.

As time went on, his defense of Clinton became almost apologetic. In a 2009 interview with Fox News’s Sean Hannity, Trump said the economy “did great under Ronald Reagan. And it did great under Bill Clinton, in all fairness.”

And, in one prescient comment, Trump also seemed to express sympathy for attacks that, nearly twenty years later, he would make his own.

“This guy has got to be the toughest guy to take the kind of abuse that he has taken. Can you imagine going home to Hillary on a nightly basis with the kinds of things being said?” Trump said in 1997 on CNN’s Larry King Live.

Contributing: Eliza Collins