A week into President Trump’s administration, the United States’ relationship with Mexico, its third-largest trading partner, is in shambles. The partnership is threatened by the conceivable collapse of a long-standing trade agreement, an immigration crackdown and the imposition of “border adjusted” taxes to fund the erection of a massive border wall that Mexico opposes. The week will end with the indefinite postponement of a meeting between Trump and his Mexican counterpart, Enrique Peña Nieto, a diplomatic rift of a magnitude not seen in decades.

Most of the fault lies with Trump, who has treated Mexico and its government with a condescension reminiscent of the worst version of America’s myopic imperialism. For Trump, Mexico has become the schoolyard’s weakling, a useful designated villain to fuel nativist fears before and after the election.

But it takes two sides for a bilateral crisis, and Peña Nieto has not done himself or his country any favors. Peña Nieto has never known what to make of Trump. In the past year and a half, through the barrage of Trumpian abuse, Mexico’s government has swayed from indifference to appeasement and back to being timidly cross. For Peña Nieto, engagement with Trump has been a disaster, perhaps the last nail in the coffin of an unpopular presidency.

Peña Nieto has only himself to blame. In the summer, in a decision that baffled the world — and especially baffled Mexicans — Peña Nieto invited Trump to visit Mexico City. It was a perplexing decision. After all, by the end of August, the Trump campaign was struggling to emerge from costly self-inflicted wounds, and Democratic presidential nominee Hillary Clinton had extended her lead in the polls. Trump needed to turn the page, and he did so in Mexico.  

Trump, who had never formally met a foreign head of state as a candidate, seized on the opportunity to be seen with Peña Nieto. Mindful of the optics of politics, he rightly interpreted the meeting as perhaps his best chance to convey gravitas and legitimacy. In that, he succeeded.

For Peña Nieto, the meeting presented a different set of challenges. Faced with a man who had gleefully insulted Mexicans for months, Peña Nieto could emerge unscathed only if he either elicited an apology from Trump or if he stated, in no uncertain terms, the country’s unwillingness to cooperate with Trump’s punitive immigration and border security agenda. Peña Nieto did neither. He allowed Trump to talk about the border wall, unchallenged, and then shook his hand.

Peña Nieto and his government have struggled to emerge from the shadow of that precedence of weakness. After the election, Trump has insisted on using Mexico as a punching bag on trade, immigration and national security. The country was there, hardly hidden between the lines, in Trump’s “America First,” crack-down-on-crime roar of an inaugural speech. And it has played a starring role in the new U.S. president’s isolationist narrative, be it through executive actions on immigration, the vow to radically renegotiate the North American Free Trade Agreement or the infamous wall.

Behind his rhetorical niceties, Trump has continued to treat Mexico’s government with disdain and arrogance. This week was worse than anything in the campaign. In an unprecedented slight in the modern history of the two countries, he formally announced the wall on the same day that Mexico’s ministers of the economy and foreign affairs had arrived in Washington for high-level talks on trade. Faced with such astounding undiplomatic vulgarity, Peña Nieto had no choice but to respond. He did so by posting a short video on Twitter — as if he could outdo Trump on the U.S. president’s favorite platform — in which he demanded “respect” for his country and hinted at postponing next week’s meeting in Washington. And then on Thursday, Trump pounced on Peña Nieto’s lack of resolve and all but erased the meeting from the schedule. Mexico’s president followed with a tweet of his own, announcing his own decision to cancel his trip north. After months of witnessing ill-advised concessions, many Mexicans applauded Peña Nieto’s decision to scratch his visit to Washington. By then, though, Trump had seized the narrative’s upper hand. The bully strutted about, still unopposed.

What is Peña Nieto to do? Of course, he should use all of the tools at his disposal to resist Trump’s bellicose approach to trade and national security. Mexico is no banana republic. Quite the contrary: Despite its troubles, it’s a vibrant nation with assets both real and symbolic to put in play. Peña Nieto should, once and for all, dispense with any hope of appeasement and learn to handle his antagonist’s binary, adversarial mind-set.

Perhaps a good place to start is by looking at the fights Trump has not been willing to pick. There is a reason Trump has not been anywhere near as harsh on China, the other potential bully in the yard. On paper, it would make sense to do so: After all, with a deficit five times that of Mexico, China accounts for about half of America’s trade imbalance.

The difference, of course, is strength. The Chinese have shown no willingness to engage in any negotiation that begins with absolute acquiescence to Trump’s demands. If only Mexico would follow suit.

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