WATCH: Trump Once Again Insults the City He's Speaking In

Donald Trump has a history of insulting his hosts whenever he leaves his safe spaces of Mar-a-Lago or Trump Tower. 

He famously insulted the city of Milwaukee just days before showing up there for the Republican National Convention in July. At the time, President Joe Biden was still the Democratic nominee, and the DNC took out ads on Milwaukee buses slamming Trump's comments.

On Thursday, Trump was in the must-win battleground state of Michigan to speak to the Detroit Economic Club, where he rambled incoherently and insulted the city. As he blathered on about China being a developing nation, Trump said: “Well, we’re a developing nation too, just take a look at Detroit. Detroit’s a developing area more than most places in China.”

He later warned the crowd that if Vice President Kamala Harris wins on November 5th, “Our whole country will end up being like Detroit if she’s your president. You’re going to have a mess on your hands,” Trump said.

Guess how well that sat with the residents of Detroit?

Michigan governor Gretchen Whitmer posted on Twitter that “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. So keep Detroit out of your mouth. And you better believe Detroiters won’t forget this in November.”

The Harris/Walz campaign has already capitalized on Trump's insults, turning it into an ad voiced by actor and Detroit native Courtney B. Vance.