Jeremy Fugleberg, and Chrissie Thompson

Cincinnati

Donald Trump's visit to Mexico Wednesday serves as an example of the way a Trump presidency would undermine the U.S.'s leadership as an "exceptional" nation, Hillary Clinton told veterans Wednesday.

Clinton censured Trump for "trying to make up for a year of insults and insinuations by dropping in on our neighbors for a few hours and then flying home again," as her Republican opponent headed to Mexico to test his diplomatic prowess in a visit with the country's president.

Trump has criticized some Mexican immigrants who are living in the U.S. illegally, and his signature campaign issue has been his pledge to build a wall on the U.S. border with Mexico and persuade Mexico to pay for it.

"That's not how it works," Clinton said of diplomacy and international leadership. Still, she avoided the jokes and mockery she sometimes uses when criticizing Trump and avoided saying his name in her speech to the American Legion gathering – a group that included some Trump supporters – at the Duke Energy Convention Center in Cincinnati.

After his visit to Mexico, Trump gave a fiery speech Wednesday night in Arizona generally doubling down on his immigration stances. He left open the possibility that people who came to the U.S. illegally before President Barack Obama took office might not be deported, but said his administration wouldn't make a final decision about them until its other plans were implemented. Trump next plans to fly to Cincinnati for his own address Thursday morning at the American Legion convention and a midday rally in Wilmington.

The two candidates are returning to Ohio as polls show them locked in a tight race in the quintessential swing state. Clinton has just under a 4-percentage-point lead over Trump in the Real Clear Politics average of Ohio polls in the last month. Her lead over Trump nationally is larger, more than 5 percentage points, and she is dominating in swing states such as Pennsylvania, Michigan and New Hampshire.

In Cincinnati, Clinton argued Trump has rejected American exceptionalism, the notion that the U.S. has a special role in the world as a leader and purveyor of democracy. The principle has traditionally been championed by Republicans, whom Clinton is trying to woo, and Trump has drawn on the principle in some ways, such as by insisting that America strive to become "great" again.

But Trump generally has opposed the use of the term and rejected the principle that the U.S. is better than other countries, to whom he routinely says the U.S. is losing.

"My opponent is wrong when he says that America is no longer great," Clinton said Wednesday, echoing the feelings of many devotees of American exceptionalism. They advocate for more engagement of the U.S. internationally to spread democratic ideals, while Trump has often taken a more isolationist approach.

That approach would hurt the U.S.'s standing, Clinton said, vowing to keep the U.S. the "greatest country on Earth."

“Our power comes with a responsibility to lead humbly, thoughtfully and with a fierce commitment to our values," she said. "When America fails to lead, we leave a vacuum.”

Several convention attendees wouldn't speak on the record about Clinton and her speech, citing the Legion's non-partisan nature. But some were privately critical of her foreign policy and veterans affairs record.

"I'm in the minority in this bunch," said Robert John of Chambersburg, Pennsylvania, who said he's been a Clinton supporter since 2008.

He characterized as weak the applause given to Clinton, although he noted it was a more respectful welcome than she had received at a Veterans of Foreign Wars convention in North Carolina in July. There, she was heckled by a few members of the crowd.

But even John thought Clinton went too far in references to Trump. According to John and several other attendees, both candidates' campaigns had been instructed by the American Legion to limit political punches in their speeches at the convention.

"When you mention the other person, that goes over the line," John said. "But they have Trump tomorrow. I'm sure he won't pull any punches."

Rick Sucee of Bellingham, Washington, said he is undecided on who to support. But Trump has his ear. Sucee is attracted to the GOP candidate's immigration proposals and hopes his shoot-from-the-hip rhetoric is just an act.

"That's what I'm concerned about," he said. "But I'm trying to look at the whole picture."

Unlike others The Enquirer spoke to at the convention, Sucee he said he had admired Clinton's service as a U.S. senator, something he said he witnessed personally on Capitol Hill visits. He also acknowledged her experience as secretary of state.

"She certainly knows how the government works," he said.

To U.S. Rep. Warren Davidson, R-Troy, Clinton's work as secretary of state doesn't back her words.

“We witnessed Hillary’s foreign policy prowess during her time as Secretary of State and it was an absolute disaster," Davidson, an Army veteran, said in a statement the Trump campaign distributed ahead of Clinton's speech. "The Obama-Clinton strategy of ‘leading from behind’ set the table for ISIS to grow. She routinely compromised classified information on her private e-mail servers, and it appears she traded access to the State Department for donations to the Clinton Foundation."