For the first half-hour of the great debate Donald Trump killed. He spun out lines and lines of message track and it seemed every move Hillary Clinton made only got her more and more tangled up in it.

Her vaunted experience was all the bad kind, Trump said, and he pegged her as a career politician who'd spent 30 years at the birth of every failure that now torments the country and the world.

When Trump talked jobs for working people and likened his tax-cutting philosophy to Ronald Reagan's, Clinton sputtered something about "Trumped up, trickle down" that sounded a little too rehearsed and way too cute.

When she leaned on the economic record of her husband, the former president, as though they were teammates, and said with affected understatement, "he did a pretty good job," Trump jumped all over her and condemned Bill Clinton for having signed NAFTA, the "worst trade deal ever"— as though the Clinton teammates were actually Mr. and Mrs. Benedict Arnold.

Trump and Clinton spar over the trade deal her husband signed 1:27

It was Trump at his focused and canny best playing his strongest card: He was change; she was more of the same.

And then somewhere near the 30-minute mark he blew it.

Everyone, even Trump, knew Clinton would try to get under his skin and lure him off message and down the rabbit hole of his vanity.

Some even predicted the ploy: She'd poke through his thin skin and tweak his ego perhaps by saying he hadn't released his tax returns because he wasn't as rich as he claimed, didn't give to charity, and owed a big pile of money.

That's exactly what she did and Trump took the bait.

Clinton pushes Trump to release tax records 2:18

He could have let it pass when moderator Lester Holt upset the flow of things and asked Clinton about the private email server she'd wrongly used while secretary of state.

Surely that was an opening for Trump.

But no, Trump had his eye on the rabbit hole and down it he went.

After a few predictable words on the Clinton email scandal —"I think it's disgraceful, and believe me this country thinks it's disgraceful"— he bridged back to his taxes and financial worth.

Trump says Clinton’s email decisions were ‘disgraceful’ 0:50

Out poured a stream of unconnected thoughts about financial disclosure, buildings worth billions, leverage, under-leverage, and a list of banks he could come up with to make a point that wasn't quite clear.

It ended up here: "I have a tremendous income," he said, "and the reason I say that is not in a braggadocious way, it's because it's about time that this country had somebody running it that has an idea about money."

He effectively took a pass on the Clinton email scandal so that he could talk to the American people in the language of a Wall Street banker and use a fancy word like braggadocious.

Birther, climate change theories bite Trump

It got worse.

During the discussion on race relations Trump again tried to argue that he had forced President Barack Obama to cough up his birth certificate in order to rid America of the scourge of birtherism – as though he deserved thanks for pulling the country out from under the dark cloud he'd created.

Trump asked about his persistence in questioning Obama’s place of birth 0:57

The reality is that Trump built his political career by encouraging doubts about the legitimacy of the first black president. And years after he forced Obama to produce his birth certificate, Trump was still questioning its authenticity.

He didn't acknowledge the truth — Obama was born in Hawaii — until a few days ago. And he only did that so he wouldn't have to talk about it anymore as a campaign issue. And yet there he was last night talking about it again.

And so viewers heard Clinton say in a matter of fact way last night that the Republican's 2016 nominee has a long history of racist behaviour.

Plus, they heard Trump still insisting he was always opposed to the Iraq invasion even though any fool can Google up the audiotape of him telling Howard Stern the opposite.

Democratic presidential nominee Hillary Clinton tried to co-opt some of the accomplishments of Bill Clinton's White House, to limited effect, but found her footing with her vast advantage in foreign affairs knowledge later in the debate. (Joe Raedle/Getty Images)

And finally they heard him deny he'd ever said climate change was a conspiracy invented by the Chinese to undermine the American economy, even though that's exactly what he said on Twitter at precisely 2:15 p.m. ET on Nov. 6, 2012. You can look it up.

By then he was a long, long way from the message track where he'd begun.

Meanwhile, Clinton had recovered from her rocky start and toward the end of the evening was playing the calm, competent one as she showed off her wonky side in a spray of details about foreign affairs.

By the end of the week public opinion polls might tell us whether that means she won the debate.

But for the moment we can see more clearly that Clinton does better when she is running against a wildly boastful prevaricator than she does when she's running against change. Presumably that's what the Trump team will be telling him today.