"Until a couple months ago, I thought we had very similar cultures. Our culture here looks more like Texas than California or any other state in the United States," he said. But now, he questions if they're as similar as he once thought.
Earlier this year, the export director drove to Austin to attend a business conference.
For the first time, even with his SENTRI expedited pass for low-risk travelers, he was held up at the border. He said he's had multiple friends tell the same kind of story in recent weeks. And he said a friend's visa was revoked because he made negative comments about Trump.
These kinds of stories lead to national paranoia.
"Culturally they're changing the rules to everyone. On this side, we're just waiting to see how the rules are going to change and hoping they change the quickest possible," the businessman said. "But really, it's shocking."
To balance things out, he said his company is now switching gears to look at Central and South America for potential buyers.
Cardenas and Horvath also mentioned that maybe it was time for Mexico to start looking for other treaties, other solutions, should it get shut out of U.S. commerce. But maybe it's still too soon -- they couldn't say for sure.
"We can't plan out from here to two or three years ahead, like we did before, well now we can't. We're planning no more than 6 months ahead, and most of the time, not even that far," said Alberto Leal, who works at the Vivati finance firm.
Historically, the United States has been known as a global leader in free trade. For Monterrey, the free trade capital of Mexico, talks of restrictive trade measures are a stunning role reversal.
"It's such an irony that because of the United States and the push it had in that era -- it opened up countries and the market. It's incredible that today it's heading in the reverse. It's shocking," said Pedro David Martinez, the founder of Regius Capital in Monterrey.
"We have a person who wants to reverse more than 50 years of global integration in one week," Martinez said. "This is the problem."
'Stronger this way' Out in the northern colonias of Monterrey, a group of men shook their heads in conversation, white corn residue on their hands like chalk. Eduardo Lopez sat on a pail and scraped kernels from a corn husk. His brother, Margarito Lopez Marin, stood nearby watching as Lucas Cristobal, a local vendor, stuffed corn into a produce bag.
Businessmen of a different stock than the venture capitalists and finance men from downtown, they too were talking about Trump, and what their futures will look like if his promises continue to unravel into reality.
Will the value of the peso, which has been declining since Trump's election, continue its downward trajectory? Will the inflation of gasoline prices -- caused in part by the weakening of Mexican currency -- bring up the cost of other consumer goods too? And can Lopez still count on being able to visit his family members who live in Dallas?
"Why does he have to treat us like this?" Lopez said.
These are the questions that plague them. A conversation of sentences ending in question marks brought on by the quickly changing politics of the United States.
"I don't know what thoughts he has, or where this is going," Cristobal said, shrugging. "But we are Mexicans and we should all be like brothers. We don't like it that another person and country comes here to hurt us."
"He's not thinking of others like us. He's thinking of himself and what he wants to do," Lopez said.
The workers have seen the news--they know Mexico relations became a cornerstone of Trump's presidential campaign. They remember what he said in 2015: "They're bringing drugs. They're bringing crime. They're rapists. And some, I assume, are good people."
And so they, like many Mexicans across the country and across economic divides, have decided to come together in the face of a common opponent.
"We're united because we don't want to let him to dominate us here. We have our country and we're going to defend our country and countrymen. And if he messes with them over there, he's messing with us, too," Lopez Marin said. "A lot of us have family there and we don't want them to get hurt there either."
Later in the day, Cristobal will sell his corn as elote, with cheese, chili and lime in a cup. And the Lopez brothers will drop off the rest with a distributor, who will take some of that corn up to cities and towns across the U.S. Cristobal said his friends on Facebook have been sharing Mexican flags in solidarity for their country.
"We just want to work and take care of our family. But unfortunately they think we're thieves," Lopez Marin said.
Miles away, women in a manufacturing plant toil to create protective gear that would get shipped across Mexico. Working inside, Olivia Guerrero Gonzalez performs the same task over and over -- smoothing out perfectly round shapes of dark glass with an old piece of machinery.
Just thinking about her country fighting for itself makes her smile.
"We're uniting more and we are stronger this way," she said.
But then her face tightens.
She recalled Trump's book, "The Art of the Deal," when he spoke about crushing the adversaries who are weak and negotiating with those who are strong.
"This is what he's doing -- he's crushing Mexico," Gonzalez said. "He thinks we're weak. He thinks we're weak because he doesn't know us."
"I want this man to study the history of Mexico. So that he can see everything we've done. So he can value us as people."