The U.S. President Donald Trump's proposal to separate the United States from Mexico with a wall on the country's southern border was one of the controversial pledges he made during the campaign season in the run-up to the November 2016 presidential polls.

President Trump had repeatedly denigrated the Mexican immigrants and vowed to block immigration from Mexico through this initiative. His wall project is now in the offing and Trump says they are the Mexicans who will pay for its construction. Mexican President Enrique Peña Nieto said the country will never pay for it. The executive order 13767 signed by the U.S. president on 25 January 2017 lays the groundwork for the commencement of the extension of the border wall. In March 2018, President Trump paid visit to the border wall prototypes being installed in San Diego.

A Mexican political scientist says the wall and the so-called Muslim ban are connected ideas and President Trump intends to appeal to his constituency by pursuing them.

Dr Salvador Vázquez del Mercado is a Conacyt professor in the National Laboratory of Public Policy (LNPP) at the Center for Academic Research and Teaching (CIDE) in Mexico City. Previously, he had worked in the Office of the President of Mexico and in the Institute of Law Studies of the National University of Mexico. He has a PhD in political science from Northwestern University, in Evanston, Illinois.

I did a brief interview with Dr Salvador Vázquez del Mercado about President Trump's wall project and the future of Mexico-U.S. relations. What follows is the text of the interview.

Q: Why do you think President Donald Trump proposed to erect a wall to separate the United States from Mexico? Do you see any connection between the wall project and his Muslim ban, which blocks the entry into the United States, of the nationals of seven Muslim-majority countries?

A: Of course there is a connection between the wall and the so-called Muslim ban; both ideas are aimed at signalling to poor, white voter’s that Trump intends to cater to their material and cultural insecurities. He made those promises during the campaign and now he intends to fulfil them, whatever their cost.

Q: Is turning immigration into a national security concern and portraying migrants fleeing war, mayhem, mistreatment and discrimination at home to seek refuge in countries like the United States, which have robust democratic institutions, as threats that should be deterred, a right way of approaching this issue?

A: I don’t believe it is, and I’m not an expert of migration – a more humane and responsible solution would be preferable. Yet, looking at the cost that Merkel paid for admitting Middle Eastern refugees into Germany, it is worth considering the political ripple effects that a more open policy can have on the mood of those who’d rather not see people from other parts of the world move in. A proper solution has to balance a humane policy with the electoral effects it might have among voters of a more nativist bend – it’s probably not an easy balance to strike.

Q: Do you believe that the United States, the world's most thriving economy, has a moral obligation to accommodate and help the refugees and migrants who want to have safer and better lives and turn to this country in search of protection and security?

A: I do. But again, that may be a little much to ask from a President who does not care about such things and seems interested in catering to the preferences of a strong, but vocal, minority who actually votes for him.

Q: President Trump had mentioned that the Mexicans will pay for the wall to be built along the Mexico-United States border. Department of Homeland Security estimated that it needs $21.6 billion to be built and Trump has suggested that by imposing a 20% tariff on Mexican goods or directly, they will be the Mexicans who will pay for it. What do you make of his assertions?

A: I don’t believe that the Mexican government would ever agree to pay for the expenses of the Wall in any shape or form. Such topics are off the table in the on-going negotiations of NAFTA. Trump painted himself into a corner by asserting during the campaign that he’d make the Mexican government pay for the wall, which seems to have surprising staying power with his nativist electorate and even perhaps with himself, even in the face of all the evidence that a wall would be useless and incredibly costly. Thus, he keeps on insisting on it.

Q: How do you see the current status of Mexico-U.S. relations? Mexico has conventionally maintained close and amicable ties with the United States and in popular culture, Mexico is referred to as a very "Western" country in Latin America. Does Trump's threats and his wall project and the fiery rhetoric exchanged between him and President Nieto mean that the close relations are about to vanish?

A: President Peña is about to leave office, we’ll be having elections next July. The candidate with the highest probability of winning the election, -- see the Bloomberg poll tracker, I collaborated in its design –, Andrés Manuel López Obrador, has taken a rather nationalistic tone and is regarded by some to be a populist who might endanger the relationship with the U.S. I don’t agree with such assessments, not entirely. He has said that NAFTA should be finalized after he takes office but nothing, to my knowledge, which is openly anti-American. It’s hard to predict what will happen after he takes office.

Mexican government would never agree to pay for the expenses of the Wall: Salvador Vazquez del Mercado