​Forget, for a moment, the ambiguity over whether Donald Trump's "great border wall" might actually be a "virtual" barrier, as some of his surrogates have suggested.

Ignore the Republican presidential nominee's lack of details about how a proposed "deportation force" would round up the about 11 million people estimated by Homeland Security to be living illegally in the U.S.

And disregard hints last week that Trump might consider "a softening" on allowing undocumented immigrants to stay in the country, provided they pay back taxes.

If you took Trump at his word on Wednesday night, hours after meeting with President Enrique Pena Nieto in Mexico, confusion over those matters would become part of the muddled past. Trump's so-called major immigration policy speech in Arizona was his chance to introduce something else: clarity and moderation.

He flirted with clarity, laying out a 10-point plan. But he outright spurned a more moderate tone, reaffirming previous tough rhetoric on illegal immigration that has found traction among a core base of white males. Trump leads Democratic presidential candidate Hillary Clinton 76-14 among white men without college degrees, according to Washington Post-ABC polling.

Trump: 'Zero tolerance for criminal aliens!'1:01

"I'm going to deliver a detailed policy address on one of the greatest challenges facing our country today," Trump said Wednesday, speaking in the state that adopted Senate Bill 1070, considered the harshest anti-immigration law in the U.S. when it passed in 2010.

"Are you ready?" Trump teased, amid cheers. "Are. You. Ready!"

But political observers seeking a lucid immigration policy instead heard "the same old song," says Laura Gomez, an expert on Mexican-American immigration and dean of social sciences at the University of California in Los Angeles.

"He promised a policy speech, but there was nothing specific in his points."

'There will be no amnesty'

The wall along the southern border? "Mexico will pay for the wall," Trump vowed again, adding that it would be "impenetrable" and "physical," replete with "the best technology" such as tunnel sensors.

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The "new deportation task force"? It's coming, along with 5,000 more border patrol agents and three times more Immigration and Customs Enforcement officers, he said, without elaborating on who might foot that bill.

As for amnesty. "There will be no amnesty," Trump said. "Our message to the world will be this: You cannot obtain legal status or become a citizen of the United States by illegally entering our country." (Last week, he told Fox News host Sean Hannity that his government could "work with" undocumented immigrants who can pay their back taxes.)

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Trump supporters pray during a campaign rally in Phoenix. During his speech, he reaffirmed his hardline stance on illegal immigration. (Carlo Allegri/Reuters)

Those who expected Trump to broaden his base with Wednesday's speech are likely disappointed, says former Republican strategist Jarryd Gonzales.

"Trump's speech was USDA prime grade red meat for the Republican base. It was a hardline speech that scored well among white males, did nothing to expand his support of women or millennials, and continued to alienate the fastest-growing population in the U.S. — Latinos."

Instead of running a "typical general election" model to appeal to a larger electorate, Gonzales says, Trump appeared to have chosen the "dance with the ones who brung you strategy," deepening his appeal among immigration-centred Republicans.

Gomez noted that about two-thirds of Hispanic voters in the 2008 and 2012 elections voted for U.S. President Barack Obama. A more moderate tone from Trump might have helped him capture a more conservative, Republican bloc of Hispanic voters.

"The question now is how much of a drop-off will there be? How many Hispanics will leave the Republican Party now?" she says. "That might have been the audience tonight [Wednesday] waiting to see if there would be any softening of his position."

The fallout among Hispanic conservatives was almost immediate. According to a report by Politico, major Latino surrogates for Trump — among them Jacob Monty, who served on Trump's National Hispanic Advisory Council, and Alfonso Aguilar, who heads the Latino Partnership for Conservative Principles — were reconsidering their support. Monty reportedly resigned following Trump's speech.

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Trump hugs a woman whose child was killed by a person living in the country without legal permission, after delivering his immigration policy speech. (Matt York/Associated Press)

Luis Rubio, a global fellow with the Wilson Center's Mexico institute, summed up the tone of Trump's speech as "hardline all the way."

"He'll alienate independents and strengthen his core constituency," Rubio said from Mexico City.  

The speech was vintage Trump, in that it was a clear departure from what appeared to be a shift towards moderation last week. In a particularly remarkable televised moment on Fox News host Sean Hannity's immigration town hall, he even took a live poll of the Texas audience, apparently to test out a possible immigration policy pivot.

Watch Trump take a live poll on immigration policy:

Trump began by asking whether otherwise law-abiding illegal immigrants ought to be "thrown out," or shown some leniency.

"I'll ask the audience," Trump announced. "You have somebody who's terrific who's been here…."

"Twenty years," Hannity offered.

"Right, long time," Trump continued. "Long court proceeding, long everything, OK? In other words, to get them out. Can we go through a process? Or do you think they have to get out? Tell me. I mean, I don't know. You tell me."

Gomez also watched the clip.

"He tried floating [an alternative to deportation] about three times, but only got the 'deport 'em' audience more riled up," she said.

With just 67 days to go until election day, it has become increasingly crucial for Trump to be unequivocal about the linchpin issue of his campaign.

"Trump had still not made a definition of what he meant by his immigration policy," Rubio said. "He needed to define that more specifically."

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Mexican President Enrique Pena Nieto and Trump shake hands after a joint statement at Los Pinos, the presidential official residence, in Mexico City on Wednesday. (Dario Lopez-Mills/Associated Press)

More specifics, 'more enemies'

The problem with doing so, according to Rubio, is that he risks either alienating a base of hardline supporters demanding tough action against illegal residents, or turning off the moderate conservatives and independents he needs to win.

"The more specifics he provides, the more friends he secures," Rubio says, "and the more enemies he guarantees."

As far as Tucson, Ariz., Trump supporter Bill Beard is concerned, details are overrated. The chairman of the Pima County Republican Party hasn't thought much beyond Trump's fundamental approach of "fixing the immigration laws."

Trump's speech reaffirmed the red-meat stance on immigration for which Beard has long supported the Republican candidate. He's less worried about policy specifics.

"Frankly, I think for the average voter out there, they're not concerned with the details of having Mexico pay to build the wall," Beard says. "The fundamental thing is Trump is going to make Mexico pay for the wall. I don't get caught up in the details."

Donald Trump's Arizona speech highlights1:59