Manifest destiny fueled US aggression against Mexico

President Polk deliberately provoked war with Mexico

After Mexico refused to sell California and New Mexico, President James K. Polk ordered US troops into disputed territory between the Nueces River and the Rio Grande—knowing it would likely spark a conflict. When fighting broke out, he used it to justify declaring war.

How the US took half of Mexico

In just two years, the United States redrew the map of North America. Sparked by border disputes in Texas and fueled by President James Polk’s drive for expansion, the Mexican–American War (1846–1848) reshaped both nations.

American annexation of Texas eventually sparked war with Mexico

After Texas won independence from Mexico in 1836, the US annexed it in 1845—despite Mexico’s refusal to recognize Texas as separate. That annexation, combined with a heated border dispute, triggered the Mexican-American War the following year.

Mexico’s political chaos weakened its defense against US invasion

Mexico’s post-independence instability—marked by coups, power struggles, and weak central control—left its northern frontier vulnerable. That political fragmentation shaped Mexico’s unpreparedness during the Mexican-American War and helped enable US conquest.

The Monroe Doctrine helped lead to the American occupation of territory abroad

This podcast explores how the policy motivated a century of US military intervention throughout Latin America, the Caribbean, and the Pacific—covering the annexation of Hawaii, the Spanish-American War, and occupations of Cuba, Haiti, and Panama.

Zachary Taylor became a national hero during the Mexican-American War

General Zachary Taylor led US forces to key victories in northern Mexico, earning widespread fame for his leadership. His popularity from the war propelled him to the presidency in 1848.

US westward expansion—and the status of slavery in the new territories—was a major cause of the American Civil War

The addition of new western lands forced the nation to confront whether slavery would spread beyond the South. Each debate over the admission of a new state sharpened the divide between free and slaveholding regions.

US troops committed widespread atrocities during the Mexican-American War

American volunteer regiments frequently looted towns, raped civilians, and executed prisoners—especially in occupied northern Mexico. Historians have documented how racial hatred and impunity fueled war crimes that were rarely punished by military leadership.

Mexico admired Lincoln for opposing the war and supporting Mexican sovereignty

As a congressman, Abraham Lincoln condemned the Mexican-American War as unjust. Years later, as president, he backed Mexico’s fight against French occupation. His principled stance earned enduring respect and monuments across Mexico.

France invaded Mexico to install a puppet monarchy and recover debt

Napoleon III used Mexico's default on foreign loans as cover for a larger imperial ambition: overthrowing President Benito Juárez's government and installing a French-backed monarchy. The Mexican army's surprise victory at Puebla helped delay those plans by nearly a year.

Support for slavery helped drive Texas to revolt against Mexico

Mexico abolished slavery in 1829, but many Anglo-American settlers in Texas brought enslaved people and refused to comply. Their desire to preserve slavery was a major factor in Texas’s 1836 rebellion and independence from Mexico.

Irish immigrants deserted the US Army to fight for Mexico

During the Mexican-American War, hundreds of Irish Catholic immigrants—facing discrimination in the US Army—defected to Mexico and formed the Saint Patrick’s Battalion. Though many were captured and executed, they remain honored as heroes in Mexico.

See the path Spanish conquistadors took to conquer the Aztecs

Spanish expeditions reached central Mexico as the Aztec Empire was expanding its influence. After securing bases in the Caribbean, they advanced west into Aztec territory, triggering a cascading conflict depicted in this interactive map and timeline.

Explore the social and cultural history of the Mexican-American War

Historian Peter Guardino joins host Don Wildman to explore how the war shaped ordinary lives on both sides of the border. Drawing from The Dead March, the episode reveals how culture, class, and ideology shaped the conflict and its consequences.

US military professionalism gave America a decisive edge in the war

The professionalism and engineering expertise of West Point–trained officers—like Grant, Lee, and Meade—gave the US a major advantage in the Mexican-American War, helping them win every major battle.

How the US entered WWI in 1917

Originally taking a position of neutrality during the course of World War I, the United States of America eventually relented. Entering the war in 1917, support for the British and French had risen and Americans were incensed by Germany's overtures to Mexico and U-boat attacks that sank ships and ended American lives. See how and why the US entered WWI in this article.

As president, Thomas Jefferson expanded federal power despite opposing centralized authority

Although Jefferson argued for limited national power, his presidency expanded federal authority through actions such as the Louisiana Purchase, territorial governance, and federal enforcement—reflecting a pragmatic departure from his earlier strict interpretation of the Constitution.

Japan’s imperial expansion in Asia set the stage for war with the US

Between 1931 and 1941, Japan seized Manchuria, launched a full-scale war in China and occupied French Indochina, moves that intensified its demand for strategic resources and triggered escalating US-led embargoes—particularly the 1941 oil cutoff—which sharply raised the risk of war between the two countries.

The power and influence of the American presidency have expanded significantly over time—far beyond what the founders envisioned.

A formal declaration of war automatically triggers hundreds of statutes granting the president sweeping domestic authority

Beyond authorizing military force abroad, a formal declaration activates a wide range of domestic powers, including authority over enemy property, trade restrictions, and emergency economic authority. It also waives the 60-day time limits under the War Powers Resolution.

One Native leader tried to save his people's land by building a nation

As the US pushed westward in the 19th century, one leader of the Ojibwe people fought back not with arms but with politics, seeking to preserve his people's territory and way of life by building a formal Native nation capable of negotiating on equal footing with the US government.

Human sacrifice reinforced Aztec political control and religious belief

The Aztecs controlled a vast territory through military might and intimidation. One very key tactic of control was the ritual of human sacrifice. While an effective scare tactic, the ritual was also grounded in deeply held beliefs that the world was sustained by blood.

The Declaration was a calculated appeal for foreign allies

This article argues that the Declaration of Independence wasn’t just a statement of separation from Britain. It was a strategic message aimed at France and Spain, designed to secure military support against the far stronger British Empire.

American archaeology has a complicated legacy

Many national parks were discovered through American archaeological expeditions and, consequently, included the looting of Native American cultural sites and artifacts.

Hollywood helped fund American military activity by boosting bond sales

To help fund its WWI military activity, the US introduced Liberty Bonds—government-issued debt marketed directly to the public. Starting at $50, the campaign targeted working Americans and offered Thrift Stamps to make bond-buying more accessible. Hollywood led the charge, with stars like Charlie Chaplin and Mary Pickford boosting bond sales.

Explore the important legislation that has shaped US immigration policy

Read about pivotal immigration legislation from the 1882 Chinese Exclusion Act—the first law restricting immigration by nationality—through DACA, examining how economic conditions, national security concerns, and social attitudes shaped American immigration policy throughout history.

'Grand Canyon of the Yellowstone,' a work by American painter Thomas Moran, inspired Congress to establish Yellowstone National Park.

Explore an interactive map of battles from the American Revolution, along with detailed summaries of each engagement

The rivalry between Alexander Hamilton and Thomas Jefferson centered on federalism—the question of how much power the federal government should hold relative to the states.

Abraham Lincoln was almost assassinated weeks before his inauguration as he traveled from Illinois to DC through Baltimore in 1861; it took two independent claims for Lincoln to be convinced the threat was real

Mark Twain spent decades feuding with the US Postal Service, convinced its costs and regulations were bureaucratic overreach.

The original copy of the Declaration of Independence is not a pristine document, and even features a smudged anonymous handprint in the bottom left corner.

The United States has had a tumultuous relationship with Cuba since its 1959 revolution, highlighted by a nuclear crisis and a decades-long trade embargo.

See a 3D reconstruction of Tenochtitlan, the Aztec capital that was home to an estimated population of 200,000 to 400,000.

The story of Dollree Mapp, whose legal challenge over her 1957 conviction for possessing "obscene material" led to a major strengthening of the Fourth Amendment

Brandi Chastain, the star of the 1999 US victory over China in the 1999 Women's World Cup, was a last-second choice to take the penalty kick that sealed the victory.

A 2019 Facebook event called on attendees to "Storm Area 51, They Can't Stop All of Us," resulting in countless memes, the creation of a music festival, and eventually the arrests of those who did try to approach the area.

44% of Americans say they pray at least once a day—discover how your state's religiosity stacks up against the rest of the country.

In 2018, 26-year-old missionary John Allen Chau was killed by tribesmen after attempting to reach and evangelize on India's isolated North Sentinel Island

Quincy Jones' 'Big Band Bossa Nova' helped introduce bossa nova—a jazz-influenced Brazilian genre—to the US

Salvador Dalí believed he was his own dead brother, who had died nine months before he was born

While El Niño moves warm Pacific Ocean waters east along the equator, La Niña moves them west, shifting where rainfall will become more common for months.

The Russia-Ukraine conflict is the largest ground war in Europe since World War II in casualties, forces mobilized, and displacement of civilians.

When a Paris department store hesitated to sell Estée Lauder's perfume, she 'accidentally' broke a bottle, causing the smell to spread throughout the store and shoppers to start asking to buy the scent.

Domino's Pizza's 30-minute delivery guarantee was responsible for the chain's 1980s surge, but it was discontinued after the company was found liable for delivery driver accidents.

Fireworks make a loud booming sound after exploding due to air expanding faster than the speed of sound.

The American cockroach is actually from Africa, an apparent hitchhiker aboard ships carrying enslaved people, with evidence suggesting the bug may have arrived in the New World as early as the 1600s.

Experimental hantavirus vaccines and therapies, still under development, have long been funded by the US military.

US housing costs have risen by roughly 175% between 1991 and 2026—but a growing number of Gen Zers are becoming homeowners anyway. In 2025, 4% of homebuyers were Gen Z, up from 3% the year before.

How Amazon operates a 'flywheel' business model, a self-reinforcing cycle that drives continuous growth