First Read is a morning briefing from Meet the Press and the NBC Political Unit on the day's most important political stories and why they matter.

HEMPSTEAD, NY -- Last night’s first presidential debate between Hillary Clinton and Donald Trump was a night of contrasts on policy (trade, taxes, “stop and frisk”) and personality. But maybe the biggest contrast of all was on the candidates’ preparation -- or the lack thereof. After a shaky start, Clinton was mostly prepared, disciplined, and methodical in her attacks. By contrast, after landing some early blows on trade, Trump was mostly winging it. And this exchange epitomized the difference:

TRUMP: You know, you've seen me, I've been all over the place. You decided to stay home, and that's OK [appearing to refer to Clinton’s lack of campaign events]. But I will tell you, I've been all over. And I've met some of the greatest people I'll ever meet within these [African-American] communities. And they are very, very upset with what their politicians have told them and what their politicians have done.CLINTON: I think -- I think -- I think Donald just criticized me for preparing for this debate. And, yes, I did. And you know what else I prepared for? I prepared to be president. And I think that's a good thing.

As NBC’s Benjy Sarlin and Alex Seitz-Wald write, “In a battle of preparation versus instincts, preparation won in a major way.” And it produced arguably the most lopsided debate we’ve seen in covering presidential politics.

Conservative writer John Podhoretz on Trump: “His supporters should be furious with him”

We’re sure that many diehard Trump supporters loved the unscripted, instinctive Trump. But ask yourself this: What did he do last night to add to his vote total? Conservative writer John Podhoretz, who is no fan of Trump, says, “His supporters should be furious with him, and so should the public in general. By performing this incompetently, by refusing to prepare properly for this exchange, by not learning enough to put meat on the bones of his populist case against Clinton, he displayed nothing but contempt for the people who have brought him this far.”

Five questions, five answers about last night

We asked five questions going into last night’s debate, and we got our answers:

Which Donald Trump shows up? Answer: The same Trump we’ve covered for 15 months. He started off disciplined and strong (when he was talking about trade), but he took the bait after Clinton poked him that he got $14 million from his father to start his business. Trump really never regained his composure after that.

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Which Hillary Clinton comes to play? Answer: It wasn’t her best debate performance we’ve observed over the last eight years, but it was good enough for Clinton. She was rehearsed, she was methodical, and after finding her footing she landed some powerful blows (on taxes, birtherism, and Trump’s comments on women).

How does Trump fare in his first one-on-one debate? Answer: It was easy to see how Trump thrived (or simply survived) during the crowded GOP primary debates -- a few zingers here, a dominating presence there was good enough. But he struggled going the distance with Clinton: The more the debate went on, the more Trump struggled. For someone who stresses stamina, he was the one who ran out of gas.

How does Clinton fare in facing off against the ultimate alpha male? Answer: She used a smiling smirk combined with reams of opposition research to attack Trump after he let his guard down (though her zinger on “Trumped-up trickle-down” definitely fell flat). Bottom line: As we said above, she baited Trump about his business (the $14 million from his father, taxes, not fully paying his contractors), and Trump took it.

What happens in the first 30-40 minutes (given that most memorable exchanges happen then)? Answer: While most of the top moments from last night happened in the second half of the debate, the first 30-40 minutes revealed Trump descent from disciplined start to taking the bait.

Taxes and birtherism aren’t going away

Maybe the most damaging part of last night’s debate for Trump was that it only extended the tax and birtherism stories, which are bound to come up again at the VP and second presidential debate over the next two weeks. On taxes, not only did Trump suggest that he’d release his taxes if Clinton releases her emails (so it’s not the audit after all?), he also seemed to admit that he indeed pays no taxes.

CLINTON: Third, we don't know all of his business dealings, but we have been told through investigative reporting that he owes about $650 million to Wall Street and foreign banks. Or maybe he doesn't want the American people, all of you watching tonight, to know that he's paid nothing in federal taxes, because the only years that anybody's ever seen were a couple of years when he had to turn them over to state authorities when he was trying to get a casino license, and they showed he didn't pay any federal income tax.TRUMP: That makes me smart

And on birtherism -- Trump’s longstanding charge that President Obama wasn’t born in the United States and thus potentially illegitimate to be president -- he (falsely) accused Clinton’s ’08 campaign of starting the issue. He also said he brought it to an end after getting Obama to produce his birth certificate. But he never apologized or explained what changed his mind (from 2011-2016 to two weeks ago) that Obama was indeed born in the U.S.

HOLT: I'm sorry. I'm just going to follow up -- and I will let you respond to that, because there's a lot there. But we're talking about racial healing in this segment. What do you say to Americans, people of color who...(CROSSTALK)TRUMP: Well, it was very -- I say nothing. I say nothing, because I was able to get him to produce it. He should have produced it a long time before. I say nothing.

Clinton gives a rallying cry for Latinos, but doesn’t for millennials

Meanwhile, Hillary Clinton had two weaknesses coming into last night -- enthusiasm among Latinos and enthusiasm among millennials. Well, at the end of the debate, she was able to make a rallying cry for Latinos. “One of the worst things [Trump] said was about a woman in a beauty contest. He loves beauty contests, supporting them and hanging around them. And he called this woman ‘Miss Piggy.’ Then he called her ‘Miss Housekeeping,’ because she was Latina. Donald, she has a name… Her name is Alicia Machado… And she has become a U.S. citizen, and you can bet she's going to vote this November.” (Surprisingly, on Fox News this morning, Trump doubled down and called Machado overweight. “She was the winner, and she gained a massive amount of weight, and it was a real problem.”) But Clinton was unable to give a similar rallying cry/shout-out to millennials. And she has work to do here.

On the trail

Hillary Clinton holds a day-after debate rally in Raleigh, NC at 1:00 pm ET… Donald Trump holds his own rally in Melbourne, FL at 7:00 pm ET… Bill Clinton holds a voter-registration events in Ohio… And Vice President Joe Biden campaigns for Clinton in Philadelphia.

Countdown to VP debate: 7 days

Countdown to second presidential debate: 12 days

Countdown to third presidential debate: 22 days

Countdown to Election Day: 42 days