Presumed Democratic presidential nominee Hillary Clinton ended her speech on the economy in Ohio by clobbering Donald Trump on his failed business ventures. (Reuters)

Presumed Democratic presidential nominee Hillary Clinton ended her speech on the economy in Ohio by clobbering Donald Trump on his failed business ventures. (Reuters)

Republican Donald Trump has swindled investors while stiffing and stepping on employees, contractors and others throughout a business career that should disqualify him as president, Democratic rival Hillary Clinton charged Tuesday.

Exactly the thing that Trump claims is his main qualification — his business background — is proof of values and practices that should trouble voters, Clinton said. Her speech blended criticism of Trump’s stated positions on the economy with warnings that the mogul is a big talker who has always been out for only himself.

“This is his one move,” Clinton said. “He makes over-the-top promises that if people stick with him, trust him, listen to him, put their faith in him, he’ll deliver for them. He’ll make them wildly successful. And then everything falls apart and people get hurt.”

The presumptive Democratic nominee cast the mogul as selfish, callous and glib about how he made money. She used the examples of now-defunct Trump University and Atlantic City, N.J., where Trump built several casinos that are now shuttered. Thousands lost jobs and Trump refused to pay tradesmen and others what they were owed, while he himself emerged “just fine,” Clinton charged.

“He put his name on buildings, his favorite thing to do,” Clinton said to laughter from an invited audience at a trade school classroom where auto repair is taught.

During a campaign stop in Columbus, Ohio, presumed Democratic presidential nominee Hillary Clinton slammed her opponent Donald Trump on how he plans to handle the economy. (Reuters)

She quoted Trump saying that Atlantic City was a “cash cow” for him and that he figured the fallout “was the bank’s problem,” not his.

Her address, the first policy speech of the general election season, was an attempt to attack Trump on the area of his greatest appeal — his own success, swashbuckling outsider attitude and promises that other people, and the country overall, can share in his success.

Trump scores well in polls that ask which candidate would be better at handling the economy, even though he lags Clinton in national polling overall. Just as she calls Trump unqualified to be commander-in-chief because of his ideas and temperament, she is seeking to discredit his economic ideas and call his priorities into question.

[GOP leaders alarmed by Trump’s ‘devastating’ fundraising start]

Trump’s tax plan, immigration policies and other proposals would likely throw the country into recession, while his apparent willingness to default on the national debt or print more money to cover it would ruin the credit of the United States and lead to spiraling inflation, Clinton said.

“You might think that because he has spent his life as a businessman, he might be better equipped to deal with the economy,” Clinton said in a mocking tone. “Turns out he’s dangerous there too.”

She spoke in front of new, bright-blue banners reading “Stronger Together,” her latest campaign slogan and one tailored for the general election matchup with Trump.

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Clinton planned a one-two punch this week — to attack Trump on Tuesday and then present the following day what her campaign is calling a thematic argument about why her ideas and programs are better.

For both speeches, she chose battleground states that may be up for grabs in November: Ohio and North Carolina.

Like national security, the economy is an area where Clinton is seeking a comparison with Trump that makes her look serious, experienced and presidential. But the economy is also an area in which Clinton more squarely confronts the core of Trump’s appeal as a businessman who has not held office.

Trump has said that Clinton’s economic stewardship would be “a disaster” and that his background as a dealmaker would set the United States up for success. He plans a speech Wednesday that aides have said would be a square attack on Clinton’s credentials.

As she reframes her economic arguments head to head with Trump, Clinton is also speaking indirectly to supporters of Sen. Bernie Sanders of Vermont, whose liberal economic platform shook up the Democratic race and pulled her to the left during a long primary fight this year.

Clinton’s campaign was premised on an appeal to the middle class, or those who feel themselves slipping out of it, before Trump entered the race a year ago. But it was Sanders, with his focus on the disparity between the rich and the poor, who seemed to capture the mood and imaginations of many Democrats. Sanders has not conceded defeat despite being unable to erase Clinton’s overwhelming lead among delegates before primary voting ended last week.

[An expensive reminder that Sanders still hasn’t dropped out: His Secret Service detail]

Clinton devoted several minutes Tuesday to a Sanders hobby horse — Wall Street greed — telling her audience that Trump, if elected, would again “rig” the economy to benefit Wall Street and wealthy people.

Sen. Elizabeth Warren (D-Mass.) also narrated a video released Tuesday by the liberal group MoveOn.org lambasting Trump as a “cheapskate” who won’t release his tax returns for fear that they will reveal him to have paid nothing or to be less rich than he claims.

The Democratic National Committee sent out a press release Tuesday claiming that fundraising reports released Monday show Trump is “still in it for himself.”

Clinton and outside allies are seeking to use Trump’s business background against him, particularly with women and independent voters, and particularly in swing states.

Clinton ridiculed Trump’s statements about women in the workforce in Tuesday’s speech, drawing low boos when she repeated his complaint that pregnant women are an inconvenience in business.

Clinton’s campaign has begun airing an attack ad against Trump in Ohio and seven other swing states, and it is also airing two ads that trace Clinton’s biography as a lawyer and advocate for women and children. Outside super PACs plan to highlight the stories of people who say they were wronged by the mogul’s business practices.

Trump prompted a small backlash last month when he suggested that he would try to negotiate down the cost of the national debt with the country’s creditors. The comments were widely interpreted as Trump seeking to use the possibility of debt default as leverage, which economists warned would represent an unprecedented threat to investor confidence and could affect interest rates.

Trump walked back those comments and said his views had been misrepresented.