The revelation that he may have paid no income tax for two decades sealed a disastrous week for Donald Trump that could prove fatal.
In past similar situations, Mr. Trump has pulled off incredible recoveries. But the presidential election is only five weeks away, the second leaders' debate is next Sunday, and Mr. Trump is getting more erratic by the day. Unless he reverses this trend, he could be headed for defeat.
Mr. Trump's refusal to release his tax returns has been an issue throughout the campaign. On Saturday, the New York Times revealed that it had a portion of Mr. Trump's 1995 tax return, in which he recorded such an enormous loss (more than $900-million) that he could have been exempt from paying any federal income tax for pretty much the next two decades.
The Trump campaign released a statement that said the candidate had a "fiduciary responsibility" to pay as little tax as possible, and besides: "Mr. Trump has paid hundreds of millions of dollars in property taxes, sales and excise taxes, real estate taxes, city taxes, state taxes, employee taxes and federal taxes."
It's true Mr. Trump pays taxes other than federal income tax. So do the illegal immigrants he wants to deport.
Of course, Ms. Clinton had already raised the possibility during last Monday's debate that Mr. Trump paid no federal income tax, to which he replied: "That makes me smart." So in a sense the Times's revelation only confirms what people had already pretty much concluded.
A rhythm of accusation, punishment and recovery has settled into Mr. Trump's campaign. He took a hit in the polls in June, after accusing a judge of bias because of his Hispanic heritage. But he recovered after a solid performance at the Republican National Convention in July.
He took a hit in August, after the Democratic convention, by lashing out repeatedly at Khizr and Ghazala Khan, whose son was killed in Iraq and who accused Mr. Trump of stigmatizing Muslims.
But he recovered in September when the focus shifted to Hillary Clinton's health, after she almost fainted at the 9/11 commemoration, and later acknowledged she had pneumonia.
Last week, having lost the presidential nominees' debate – a Fox News poll said six in 10 voters thought Ms. Clinton had won; two in 10 gave it to Mr. Trump – Mr. Trump went after Alicia Machado. During the debate, Ms. Clinton accused Mr. Trump of bullying and shaming the former Miss Universe.
Rather than let it go, Mr. Trump repeatedly counterattacked last week, accusing Ms. Machado of being a troublesome Miss Universe who become overweight, culminating Friday in a middle-of-the-night slew of tweets in which he called Ms. Machado "disgusting" and accused her (falsely, it appears) of making a sex tape. The latest Fox News poll has Ms. Clinton ahead by five points.
There is still time for yet another recovery, but to achieve that Mr. Trump must somehow change the narrative away from his erratic and abusive behaviour. Instead, he kept it firmly in place this weekend with a performance at a rally in Manheim, Pa., in which he mocked Ms. Clinton's health – "Here's a woman, she's supposed to fight all of these different things, and she can't make it 15 feet to her car,"– her fidelity to her husband – "I don't even think she's loyal to Bill, if you want to know the truth. And really folks, really, why should she be?"– and her sanity – "She's got a bad temperament. She could be crazy. She could actually be crazy." But it's not Ms. Clinton who's acting crazy right now.
In this election, whichever one of these deeply unpopular candidates is dominating the headlines is losing. So next Sunday, in the second debate, Mr. Trump will try to shift the focus back to Ms. Clinton's character and stamina.
But if you're a woman, you can't think much of the way Donald Trump has treated women this week. If you pay income tax – well, you're a schmuck, because Donald Trump sure doesn't.
This sort of thing can cost you an election.