The First American Expansionism

Map of the Louisiana Purchase, 1803. Photo: Wikimedia Commons

On February 2, the U.S. government issued a statement boasting about the war against Mexico, through which it stripped us of more than half of our territory. Trump described that war as “a legendary victory” that affirmed Manifest Destiny: “Our nation was destined by divine providence to expand to the golden shores of the Pacific Ocean…”

The statement echoes the official version of U.S. historiography, which has distorted what actually happened. Trump repeats that Mexican troops ambushed U.S. soldiers on the Rio Grande—as they call the Rio Bravo—forcing President James Polk to act to defend U.S. security, dignity, and sovereignty by declaring war on Mexico.

Although a figure like Donald Trump should no longer surprise us, it is difficult to understand what his goal is with a statement that offends and hurts our country, as well as the infamous racist message he posted on social media days later mocking Barack and Michelle Obama—though that is a topic for another discussion.

It is worth recalling the immediate precursor to the war in which we lost more than half of our territory: the seizure of Texas.

A constant in the history of the United States is territorial expansion. From its origins, the Anglo-Saxon groups that arrived in the northwest of the American continent settled and extended their dominions through occupation, purchase, war, and the dispossession of lands that were not theirs. Countless Indigenous peoples were displaced—many of them annihilated—from the places where they had lived for centuries. Other territories had been conquered and colonized by Spain, Portugal, England, and the Netherlands, which had arrived before the Americans, though they had followed the same pattern of dispossessing Indigenous territories.

Once the 13 Anglo-Saxon colonies gained independence from England in 1776, their ambition to expand southward, westward, and northward intensified. The new nation began its expansion northwest of the Ohio River. Between 1795 and 1809 alone, they seized 20 million hectares of Indigenous land. This led to the creation of the states of Ohio, Michigan, Indiana, and Illinois.

Under President Thomas Jefferson, territorial expansion became a matter of state policy. Jefferson took advantage of a favorable international situation, as Napoleon Bonaparte’s European wars made it urgent to secure resources to finance them and because defending France’s American colonies was becoming increasingly difficult. Thus, in 1803, Napoleon offered to sell Louisiana to the United States—a vast territory twice the size of the American Union, whose northern border abutted Canada and whose southern border extended to the Gulf of Mexico. The mighty Mississippi River, strategic for river trade, flowed through that territory, and it was home to the city of New Orleans, which became the second most important port of the young nation.

The Louisiana Purchase marked a turning point in the history of that country. It attracted thousands of settlers, expanded and diversified its economy, and fueled ambitions to seize the territories to the south and west that belonged to the Spanish Empire. Jefferson was the leader who encouraged American expansionism, created a myth of conquest and appropriation of territories held by Indigenous peoples and New Spaniards, promoted colonization, and set the boundaries to be reached: to the south, as far as the Rio Grande; to the west, as far as the Pacific coast; and to the east, as far as Cuba and Puerto Rico. 

The second president, John Adams, unabashedly expressed this expansionist aim in 1804: “The people of Kentucky are full of a thirst for enterprise, and though they are not poor, they feel the same lust for plunder that drove the Romans in their heyday. Mexico glitters before our eyes. All we hope for is to rule the world.”

And indeed, the Americans initiated what would years later become Manifest Destiny: they invaded West Florida between 1810 and 1814. In the midst of Mexico’s War of Independence, they sought to capitalize on the instability caused by the struggle between insurgents and royalists, and proposed to the Spanish monarch Ferdinand VII the acquisition of East Florida. In 1819, the Spanish crown relented, and the Americans occupied the entire Florida peninsula. Ferdinand VII thought that this would appease their expansionist spirit and that they would abandon their desire to take Texas.

Very soon, the new Mexican nation realized that the Americans had not forgotten those aspirations. During the 1820s and the early years of the following decade, the thousands of settlers who occupied Texas worked tirelessly to achieve Texan independence. The strategy was similar to that employed in Florida: occupy the territory by flooding it with thousands of families, obtain land grants, claim rights that did not exist, incite the residents to revolt, and issue an ultimatum: territorial surrender through purchase or war.

Mexican governments, mired in political instability and financial bankruptcy, were unable to increase colonization of Texas or maintain military control over it. Meanwhile, the influx of Anglo-Saxon families increased, promising to respect the laws and authority of the Mexican government. In all the territories annexed by the United States since the Louisiana Purchase, the enslavement of people of African descent was the backbone of its economy. For this reason, the abolition of slavery—one of the greatest achievements of our Independence—was rejected by the Texan settlers and was one of the factors that fueled the separation.

*Director of the National Institute of Historical Studies of the Revolutions of Mexico

Original text by Felipe Ávila published in La Jornada on April 2nd, 2026.
Translation by Schools for Chiapas.

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