MEXICO CITY — The shakiest tremor U.S. President Donald J. Trump may have triggered in Mexico is not his insults or attacks. Instead, it's a renewed debate about Mexico's development. For the second time in four decades, the way Mexico's economy, indeed the country, is run has become a subject of debate. This time, however, the criticism has not come from within: it's come from the United States.

The NAFTA free-trade agreement was the culmination of changes that began with a debate in our government in the second half of the 1960s. The country had to decide whether to open the economy or keep it protected, move closer to the U.S. or keep its distance, give precedence to consumers over producers, whether to have more or less government intervention in personal and business decisions. It was, broadly, a debate on what Mexicans should do to advance the country's development. In the 1970s, Mexico expanded government, increased spending and protected the economy, decisions that produced financial crises in 1976 and 1982. We stretched the chord as much as we could, until reality snapped it.

In a setting of hyperinflation in the mid-1980s, authorities stabilized the economy and started a sinuous process of economic liberalization. Hundreds of firms were privatized, public spending was rationalized, foreign debt was renegotiated and the country opened up to imports. The hope was that a change of strategy would generate enough investment to boost growth, and increase jobs and revenue. Although the changes were radical, they failed to bring about enough of the promised investment.

NAFTA has become our doorway to the modern world

It was NAFTA that boosted the economy. It sparked a revolution in industry and exports. In spite of the many, and in some cases absolutely legitimate, criticisms of the free-trade deal, the country became an exporting powerhouse that no longer faced a balance of payment problem that had prompted crises in earlier decades. But NAFTA was much more than a trade and investment agreement — it was a window of hope and opportunity.

For the ordinary Mexican, it meant the possibility of building a modern country, a society based on the rule of law, and, above all, a ticket to development. This may explain the mix of attitudes in Mexico toward Trump today: personal contempt for him on the one hand without vulgar anti-American feelings spreading through the population; and on the other, terrible anxiety at this dream of development being shot down. The Mexican economy, which could not attain high growth rates or a significant rise in per capita GDP in all these years, exacerbated these feelings.

Keep in mind that NAFTA has more than amply attained the goals we set out for it. It has facilitated productive investment, generated a new industrial sector, boosted exports and given investors a degree of assurance on the "rules of the game." Indirectly, it has also created a feeling of clarity about the future, including for those not directly involved in NAFTA-related enterprises. In short, NAFTA has become our doorway to the modern world, and Trump's challenge is not just threatening investment but also a vision of the future most Mexicans share.

Looking down in the capital — Photo: Alejandro

NAFTA was a way to limit our rulers' powers of abuse by restricting changes to the governing laws and giving our development model credibility. It paved the way for political liberalization, which although half-hearted and uneven, has reduced the concentration of power and changed the relationship between ordinary Mexicans and their rulers. Paradoxically, NAFTA (and job opportunities in the U.S.) also allowed politicians to keep living in their little world of privilege without bothering to perform basic tasks such as creating a modern educational system and ensuring the safety of citizens.

For now, we don't know for sure what will happen to NAFTA. It has already taken a hard knock. Trump has not only exposed our characteristic political weaknesses but also destroyed the certainty that came with our "ticket to modernity."

Perceptions and hopes have now changed. Don't be surprised to hear people start speaking of closing ourselves off, retaliating against Americans, and restoring an "efficient" state, for want of a better word. The people saying this do not understand that NAFTA was much more than an economic instrument — it was our chance for a brighter future.

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