Donald Trump is "only gonna make it worse" for the United States, a man featured in a Trump ad said. View Full Caption Flikr/Gage Skidmore

CHICAGO — An ad for Donald Trump features a Chicago-area business — but the owner said the billionaire presidential candidate is "harmful," throws tantrums and doesn't have his support.

David Greene, the owner of Iron & Wire, learned of the ad last week when someone sent his employee a photo from it — featuring, to his surprise, him and his employees. By then, the ad was already being played online and had been featured on TV in battleground states.

Greene watched the ad online and didn't like what he saw: A black-and-white photo of his crew as a narrator said Trump, the Republican presidential candidate, would focus on "American workers" and making "America great again." The ad was paid for by the Rebuilding American Now PAC.

There were a few problems with the ad: Greene never agreed for the photo to be used, and he thinks Trump has spread a message of hate and pessimism he doesn't agree with.

And, oh, yeah, Greene supports Hillary Clinton in this election.

"I wasn't happy for us that we were used in the ad," Greene said. "I don't feel that he's somebody that I support for president, and I don't agree with his idea of what makes America great.

"Donald Trump thinks he knows how to make things better, but he's only going to make it worse."

Greene has run suburban Skokie-based Iron & Wire for 18 years, crafting art, furniture and staircases, among other things, throughout the city. The image used in the Trump ad was taken years ago for a video the business ended up not using. The photographer put the picture on a stock website, but it wasn't supposed to be used for political purposes, Greene said.

About two years ago, the campaign for a man running for office in Portland, Ore., asked Greene if it'd be OK to use the picture in a primary ad. That was OK because Greene agreed with the man's views, he said.

Not so with Trump — the PAC that made the ad never asked for Greene's approval, and he certainly doesn't support the candidate's views, he said. He's not sure yet what legal action, if any, he or Iron & Wire will take.

"I didn't have a problem with it when it was used for someone that I agreed with," Greene said. But Trump's campaign is different, he said: "People are working hard ... and making this country great. And upsetting relationships with other countries and inciting hate and being, frankly, unpatriotic and harassing a veteran's family who's lost a child is not the character that I want to support."

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Greene said clients have recognized the Iron & Wire team in the ad and have texted him about it. He posted on Instagram, disavowing Trump, and said people have told if they hadn't seen that they would have thought he was promoting Trump. That would be "harmful to business," he said.

"I don’t agree with his idea of slash-and-burn politics where if he doesn’t get what he wants he has a tantrum and offends world leaders or breaks trade deals," Greene said. "You need to be a statesman. I don’t think Donald Trump is a statesman. I think he’s someone who’s promoting himself."

Greene doesn't think he'll lose clients because people will find out he doesn't support Trump, he said. But he also doesn't want to spend too much time dealing with the issue since he's focused on his business, where he puts in 14-hour days.

Greene is concerned about how a Trump presidency could affect small businesses like his, though. Iron & Wire faced hard times during the Great Recession after the "nightmare mess that George Bush created," he said. It's only during the last few years that Iron & Wire has begun to thrive again.

"We really cherish the relationships that we’ve had with our clients and colleagues the last few years, and we keep each other moving forward and supporting families and supporting jobs, helping people," Greene said. "I don’t want to lose that by electing people that want to pit people against each other and have a pessimistic view of society."

Trump has repeatedly generated controversy in Chicago: He's criticized the city's violence while exaggerating statistics, his rally at UIC was canceled amid large protests, and his running mate, Indiana Gov. Mike Pence, has been critical of the city for years.

The Trump campaign did not respond to a request for comment.

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