US President Donald Trump has been told he is "no longer welcome" in Michigan after refusing to wear a face mask on camera while visiting one of the state's car factories.
Under an executive order issued by Governor Gretchen Whitmer, "any individual able to medically tolerate a face covering" must wear one "when in any enclosed public space".
Today Mr Trump visited Ypsilanti, Michigan, and toured a Ford plant which has been repurposed to manufacture ventilators and personal protective equipment.
When the President emerged to speak to the media, he was not wearing a mask.
"I had one on before. I wore one in this back area. But I didn't want to give the press the pleasure of seeing it," Mr Trump said when he was asked why.
"But I had it in the back area, I did put a mask on.
"(It's) not necessary here. Everybody's been tested and I've been tested. In fact, I was tested this morning. So it's not necessary."
Mr Trump was surrounded by Ford executives and his own staff, all of whom were wearing masks. The one exception was White House Chief of Staff Mark Meadows.
Asked whether Mr Trump was told he didn't have to wear a mask, Ford's executive chairman Bill Ford said it was "up to him".
Ms Nessel had written to Mr Trump before his visit, reminding him of Ms Whitmer's executive order.
"Anyone who has potentially been recently exposed, including the President of the United States, has not only a legal responsibility but also a social and moral responsibility to take reasonable precautions to prevent further spread of the virus," she'd told him.
Shortly after the President appeared without a mask, Ms Nessel went on CNN and condemned his decision to ignore the order. She said Mr Trump was "no longer welcome" in the state.
"Today's events were extremely disappointing, and yet totally predictable," she said.
"His own doctor, Dr (Anthony) Fauci, his own medical expert, recommends the wearing of masks in public enclosed spaces. The CDC (Centres for Disease Control and Prevention) makes that recommendation.
"In Michigan, now that is the law. In fact, a court just upheld that, just upheld the Governor's orders, just hours ago."
She was referring to Michigan's Court of Claims, which ruled Ms Whitmer did have the right to extend her state's stay-at-home order and state of emergency, throwing out a lawsuit filed by Republicans in the state legislature.
"The President is like a petulant child who refuses to follow the rules," Ms Nessel continued.
"This is no joke. I mean, you just reported that 93,000 people have died in the United States. He is in a county right now where over a hundred people have died. I am 20 minutes away from him in Wayne County, where we've had over 2300 people die.
"This is not a joke. And he's conveying the worst possible message to people who cannot afford to be on the receiving end of terrible misinformation."
Host Wolf Blitzer asked her what, exactly, that message was.
"I think the message he sent is the same message since he took office in 2017, which is, 'I don't care about you. I don't care about your health. I don't care about your safety. I don't care about your welfare. I don't care about anyone but myself,'" Ms Nessel replied.
"It sends a message that anybody can do whatever they want because, 'Look, the President did it, so why can't I?' It's a terrible message to send, it's incredibly disappointing, and it's very disrespectful to the people of our state."
Ms Nessel has previously threatened to take action against "any company" that allows people to violate the executive order. Speaking to CNN, the Attorney-General implied she would be following up on that threat.
"I think we're going to have to have a very serious conversation with Ford. They allowed the President to be in publicly enclosed spaces in violation of the order," said Ms Nessel.
"They knew exactly what the order was, and if they permitted anyone – even the President of the United States – to defy that order, I think it has serious health consequences, potentially, to their workers."
She said there had been "lengthy" negotiations between Ms Whitmer, the United Auto Workers union and the big three car companies – Ford, General Motors and Fiat Chrysler Automobiles – to ensure that "people if they went back to work, they would be safe".
"This was a promise, this was a commitment that was made by the big three to our auto workers, who have been getting sick," she said.
"We just opened up these plants again. Just on Monday, Ford already had a few plants that had to close down because people were testing positive again.
"The last thing we want to see now is for this particular plant to have to close its doors and shutter its doors again because someone may have been infected by the President."
To reiterate, Mr Trump's argument was that he had tested negative for the virus hours earlier, and therefore did not pose a threat to anyone else.
"I tested very positively, in another sense. So this morning, yeah, I tested positively toward negative. Right? So, no, I tested perfectly this morning. Meaning I tested negative," he told reporters, perhaps a little confusingly.
The point is, he was not infected.
Blitzer asked Ms Nessel to react to Mr Trump's other stated reason for removing his mask, that he "didn't want to give the press the pleasure" of seeing him with one on.
"Well it's my reaction to many of the things we hear Donald Trump say, and that is that he's a ridiculous person. And I am ashamed to have him as President of the United States of America," she responded.
"And I hope the voters of Michigan will remember this when November comes. That he didn't care about their safety; he didn't respect them enough just to engage in the very simple task, the painless task, the easy task of wearing a mask."
The President responded angrily on Twitter, calling her a "wacky do nothing Attorney-General" who was taking her "stupidity" out on Ford.
Mr Trump has repeatedly clashed with Ms Whitmer and her state government throughout the pandemic. Just yesterday, he accused Secretary of State Jocelyn Benson of going "rogue", and threatened to cut off Michigan's federal funding.
He was agitated by Ms Benson's announcement that Michigan will send an absentee ballot application to every registered voter ahead of November's general election, giving them the option to vote by mail.
The idea behind that policy is to prevent a situation – should the virus still be a problem six months from now – where people have to choose between going to the polls and risking infection, or staying home and losing the chance to vote at all.
Mr Trump believes mail voting could lead to widespread fraud.
"If we're talking about the mail-in ballots, if people mail in ballots, there's a lot of illegality. They send in ballots that – they harvest ballots. You know all about harvesting. And they do lots of bad things," Mr Trump told reporters at the White House yesterday.
"Ideally people go out and vote. Now, if you need a mail-in ballot – for example, I'm in the White House and I have to send a ballot to Florida. That makes sense. So if you need it for some reason. Or if somebody's not well, that's one thing.
"But when you send out 7.7 million mail-in ballots, there's forgeries. There's frankly duplication, where they print ballots on the same kind of paper, the same kind of machinery and you can't tell the difference. And they send in thousands and thousands of fake ballots.
"This nation can't be going down that path, because it's a very dangerous path to go down.
"Mail-in ballots are very dangerous. There's tremendous fraud involved and tremendous illegality."
Ms Benson hit back, pointing out that her Republican counterparts in states like Iowa, Georgia Nebraska and West Virginia were also sending absentee ballot applications to their voters, but had not drawn the President's ire.
None of those states is considered likely targets for the Democrats in the election. Michigan, on the other hand, is a swing state, meaning either major party could win it.
Four years ago, Mr Trump beat Hillary Clinton there by a razor-thin margin of 11,000 votes.