Ana Maria Salazar worked at the White House as policy adviser for President Bill Clinton's special envoy for the Americas and was deputy assistant secretary of defense for drug enforcement. She writes, teaches and has anchored radio and TV news programs in Mexico since 2001. The views expressed are her own.

(CNN) Send them back. Build a wall. Trade less. That is Donald Trump's policy toward Mexico. And it creates a real headache for Mexico's leadership now that he has been chosen as the next US president.

Relations between both nations will not be easy. After all, Trump almost immediately became one of the most hated people in Mexico's history when he launched his campaign last June with these now infamous words

"When Mexico sends its people, they're not sending their best. They're not sending you. They're not sending you. They're sending people that have lots of problems, and they're bringing those problems with us. They're bringing drugs. They're bringing crime. They're rapists."

Almost 18 months later, a poll published just before the election showed that the anger had barely eased; it found that 76% of Mexicans had a bad or very bad impression of Trump.

And it wasn't just individual Mexicans who were worried. As the US results started to come in, and as it became clear that Hillary Clinton would probably lose, the value of the Mexican peso plunged close to 15%.

None of this is surprising. Donald Trump has brilliantly woven together the fear of "illegals" with other issues like crime, drugs, unemployment, low growth and even terrorism. In the process, he has made Mexico into the perfect scapegoat. And having put this theme at the center of his campaign, it is difficult to see how Trump will be able to back away from his proposals. Will he still try to build a wall? How would he pay for it? By going after remittances? Will he follow through on his pledges on deportation?

These are the types of questions that Mexican President Enrique Peña Nieto is now wrestling with. His problem, though, is twofold: How do you negotiate with one of the people whom Mexicans despise most? And how do you do so when your credibility and popularity have plunged with your own people ? (Mexicans have not forgiven Peña Nieto for inviting Trump for a visit in August ). Peña Nieto has very few tools to defend the rights of millions of Mexicans who could be deported back to Mexico, which has only increased the anger toward the President.

The one issue where Peña Nieto might have some influence over Trump is on any negotiations on the North American Trade Agreement, or NAFTA, especially once Canadian Prime Minister Justin Trudeau is included in discussions.

Clearly, Peña Nieto and Trudeau could never have imagined that at the next North American "three amigos" meeting they would be joined by global trade destroyer Donald Trump. But one lesson that can be taken from Hillary Clinton's loss is that there is an underlying, and extraordinarily strong, rejection of trade agreements among many Americans. Indeed, Clinton's stance on NAFTA (although timid compared with Bill Clinton when he was in office) may have contributed to losses in Michigan and Pennsylvania.

The other trade agreement attacked by Trump during his campaign, the Trans-Pacific Partnership, was pretty much declared dead by Senate Majority Leader Mitch McConnell , and the Senate will not move forward with the ratification of this 12 nations agreement. This means NAFTA is pretty much the only trade agreement left that President Trump will be able to give "The Art of the Deal" treatment. And that might be disastrous for Mexico, Canada AND the United States.

Will America walk away from the 2-decade-old NAFTA? It seems almost impossible to imagine; the cost in growth and jobs for both nations would simply be too high. For example, a study by the Mexico Center at the Woodrow Wilson Institute noted some half-trillion dollars in goods and services each year between both countries, "which amounts to more than a million dollars in bilateral commerce every minute." It also suggested that should the United States ditch NAFTA, it could mean the loss of some 5 million US jobs that depend on trade with Mexico.

Relations between Peña Nieto and the incoming US president at least got off to a good start, with the former congratulating President-elect Donald Trump on Wednesday, just hours after Clinton had conceded.

According to Peña Nieto, they spoke about security, cooperation and prosperity. That they talked about security is no surprise -- the uptick in violence in Mexico, as well as trafficking of heroin to the United States, will be a priority issue for both the United States and Mexico in the coming months. But the truth is that by the time Trump has picked his Mexico/Latin American policy team, and negotiations start to dismantle NAFTA, Peña Nieto will already be approaching lame duck territory, with a presidential election to take place in Mexico in 2018.

Also on the economic front, Trump threatened US companies like Ford that build vehicles in Mexico with a 35% tax. "When that [Ford] car comes back across the border into our country that now comes in free, we're gonna charge them a 35% tax. And you know what's gonna happen, they're never going to leave," he said

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The irony with such comments is that Mexico will now have to find ways to defend and support US companies from their government, if they have intentions or investments in Mexico.

But there is a potential wild card in all this. The populist, anti-establishment Andres Manuel Lopez Obrador is seen as a leading contender for Mexico's presidency. He may see a populist Trump presidency as providing an opening for his candidacy. And if he is successful, we could see a meeting between a President Donald Trump and a President Andres Manuel Lopez Obrador that would raise almost as many eyebrows here in Mexico as Trump's extraordinary win did across the border.