Republican former President Donald Trump, speaking Thursday to the Detroit Economic Club at the Motor City Casino, bashed Michigan's largest city at a time when longtime residents and many national commentators alike consider Detroit to be on an upswing.

In a long, rambling speech, Trump went on at length about the threat he believes is posed to the U.S. if Vice President Kamala Harris, the Democratic nominee, is elected in the Nov. 5 general election. At one point, after talking about trade, he veered into comments about the U.S. and its alliance with European countries in NATO, or the North Atlantic Treaty Organization, and what they contribute to the group.

He then abruptly said he didn't think that concern would be "high on her list," referring to Harris.

"I don't think anything that we're talking about today is high on her list," Trump continued. "The whole country is going to be like, you want to know the truth? It'll be like Detroit. Our whole country will end up being like Detroit if she's your president. You're going to have a mess on your hands."

He didn't mean it as a compliment, either.

Trump then went on to say Harris "destroyed San Francisco," where she served as district attorney, though he wasn't clear what he meant by that. While he didn't specifically explain what he meant in terms of Harris' effect on the U.S. − and how it would be like Detroit − he did at various times during the speech argue that her policies would lead to open borders, increased crime and drug use and the elimination of Michigan's manufacturing base.

During President Joe Biden's tenure, manufacturing has grown nationwide by about 6% and about 3% in Michigan from where it was when Trump took office. Illegal immigration, which was high through much of Biden's tenure, has recently fallen dramatically following the Biden administration toughening asylum rules.

While the crowd didn't seem to react to Trump's remark about Detroit, some local and state leaders did. On the social media platform X, Michigan House Speaker Joe Tate, D-Detroit, posted, "Donald Trump might not remember where he is right now so here’s a quick reminder about what Detroit’s all about. This is the greatest city in the country & we’ve bounced back after Trump killed our jobs, closed our businesses, & tried to throw out our votes. #Detroit threw Trump out of the White House last time and we’ll do it again."

Also posting on social media, Detroit Mayor Mike Duggan chided the former president and praised the city's progress.

"Detroit just hosted the largest NFL Draft in history, the Tigers are back in the playoffs, the Lions are headed to the Super Bowl, crime is down and our population is growing. Lots of cities should be like Detroit. And we did it all without Trump’s help," he wrote..

Democratic Gov. Gretchen Whitmer, who has often sparred with Trump, had something to say about it, too.

"Detroit is the epitome of 'grit,' defined by winners willing to get their hands dirty to build up their city and create their communities — something Donald Trump could never understand," she posted on X. "So keep Detroit out of your mouth. And you better believe Detroiters won’t forget this in November."

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State Sen. Mallory McMorrow, D-Royal Oak, also posted on X, "As a proud elected representative of tens of thousands of Detroiters… Don’t come back." (She also used an expletive that that Free Press is not repeating here.)

As to the idea of the rest of the U.S. becoming like Detroit, state Rep. Tyrone Carter, D-Detroit, told the Free Press, “I think that would be a wonderful thing for the rest of the country.”

Carter – who chairs the Detroit Caucus in the Michigan Legislature – suspects Trump’s comment was a dig at the city’s majority-Black population. “I’m sure there are some racial overtones or undertones or side tones to that,” he said.

It's not the first time Trump has used Detroit as an example of a major American city in decline and after the 2020 election, he leaned heavily into false claims that corruption in the city resulted in his loss in Michigan to President Joe Biden. As the Free Press pointed out then, however, Trump actually did better in Detroit in 2020 than he did in 2016, when he narrowly beat Hillary Clinton statewide.

Paradoxically, Trump also seemed to praise Detroit later in the speech, when he said he could be on a beach somewhere but would "rather be in Detroit with you."

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Some national outlets have suggested a resurgence in Detroit in recent months. The city's population grew last year and the incidents of violent crime dropped in 2023. Trump has also in the past courted votes in Detroit, especially among Black men. Former Mayor Kwame Kilpatrick, whose sentence on corruption charges Trump commuted before leaving office, has stumped for the former president, calling him "the best candidate."

Trump courted Black voters in the city at a roundtable discussion in June and his vice presidential running mate, U.S. Sen. JD Vance of Ohio, campaigned in the city's Eastern Market district this week.

Contact Todd Spangler: tspangler@freepress.com. Follow him on Twitter@tsspangler. Free Press staff writers John Wisely, Arpan Lobo and Paul Egan contributed to this story.

(This story was updated to add a photo.)