The United States invasion of Mexico in 1846 inflicted a painful wound that, in the 170 years that followed, turned into a scar. Donald Trump has torn it open again.

Among the many lies that he has constructed, none is more ridiculous than his attempt to contradict history by presenting the United States as a victim of Mexico, a country that supposedly steals jobs, imposes onerous treaties and sends its “bad hombres” across the border.

To confront this fake history, some Mexicans are proposing to remind Mr. Trump exactly what country was the first victim of American imperialism. They are calling for a lawsuit that would aim to nullify the Treaty of Guadalupe Hidalgo (signed on Feb. 2, 1848), in which Mexico — invaded by American soldiers, its capital occupied, its ports and customs stations seized — was forced to accept the American annexation of Texas and concede more than half the rest of Mexican territory, now including most of the states of Arizona, New Mexico and California.

This effort is being led by Cuauhtémoc Cárdenas, the elder statesman of the Mexican left. Mr. Cárdenas is convinced that the Mexican government — especially given the need to confront Mr. Trump’s aggression — has a solid legal case. In his opinion, the 1848 treaty violates essential international legal norms and a case can be brought before the International Court of Justice, proposing reparations and indemnification. And even if one admits the legal validity of much of the treaty, there are a number of crucial articles — such as those dealing with citizenship, property and the security of 100,000 Mexicans who remained on what became American territory — that have been ignored from the beginning.

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If the present Peña Nieto government does not adopt Mr. Cárdenas’s project, an opposition candidate (of either the populist left or the nationalist right) could legitimately assume it as a banner for the presidential elections of July 2018. Such a new president could make that lawsuit a reality.

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Mr. Cárdenas’s initiative may have little chance of succeeding legally, but its public impact could be considerable at a time when Mexico is being attacked unjustly by President Trump.

The United States owes Mexico and itself an honest reconsideration of its first imperial war, not only in its schools and universities but also in its museums and books. Hollywood and Broadway, which have always played an important role in shaping the American historical consciousness, should take up the issue.

Films, documentaries and memorable TV series have helped to modify the memory of two original sins, slavery and racism against African-Americans, and, with somewhat lesser attention perhaps, the racist slaughter and repression of the American Indians. A third sin should be added to these: the aggression against Mexico and the plundering of its territory.

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For us Mexicans, this is the chance for a kind of reconquest. Surely not the physical reconquest of the territories that once were ours. Nor an indemnification that should have been much greater than the feeble amount of $15 million that the American government paid, in installments, for the stolen land. We need a reconquest of the memory of that war so prodigal in atrocities inspired by racial prejudices and greed for territorial gain.

But the best and most just reparation would be American immigration reform that could open the road to citizenship for the descendants of those Mexicans who suffered the unjust loss of half their territory.

Original Article