10 Great What-Ifs of American History

Your course begins with one of the biggest what-ifs in American history: What would have changed if the Confederates had succeeded in taking Little Round Top on the second day of the Battle at Gettysburg? As you explore this introductory “counterfactual,” consider how history ripples across the ages.

America’s expansion has been called “manifest destiny,” but as you will see here, it was anything but destiny. After the Louisiana Purchase, Thomas Jefferson sent four expeditions westward - and only Lewis and Clark succeeded. Barely. See how one grizzly bear might have reshaped America, Texas, and the Lakota Nation.

World War II looms in recent American history, with President Roosevelt leading a country with isolationist leanings to a great triumph and a new role as the leader of the free world. But what if FDR had not been president? Delve into the wild politics of the 1920s and 1930s to explore a world that easily could have been.

The Apollo program is legendary for the way Americans beat the Soviets to the moon within a decade. As this lecture reveals, however, the space program’s success was as much about political will as technological advancement. Find out how a chance event with one Soviet scientist could have altered the history of space travel - and the future of two global superpowers.

It is hailed as the centerpiece of American government - but it almost didn’t happen! The US Constitution was highly controversial when it was written in 1787, and some states wanted to reject it! Find out how Federalists in New Hampshire (of all places) managed to save the Constitution and get it ratified with just a few changes to a schedule!

Contact between Old-World Europe and North America was a near-certainty, but Columbus’s voyage in 1492 relied on a number of improbabilities—beginning with his incorrect math about the size of the world. Imagine instead that the Aztecs had been able to consolidate power before the Portuguese made contact with them a few generations after Columbus had made landfall in the Americas.

We’re trained to believe the arc of history bends toward justice, and President Lincoln establishing freedom for the slaves in America is a critical step in this arc. However, Lincoln was not an abolitionist at the start of the Civil War. So, if the war had ended sooner, he might not have issued the Emancipation Proclamation. What then? Find out in this thought-provoking lecture.

At first, it might sound bizarre to imagine the United States having witch trials in the 20th century, but it didn’t happen because the Salem Witch Trials took the possibility off the table more than 300 years ago. Walk through the oddities of 1692 to see how the arguments of two ministers—and one legal loophole—created the worst witch hunt in American history.

In 1831, Nat Turner led an armed revolt across Virginia. A lengthy stopover slowed the group’s momentum and eventually the revolt was quelled. But what would have happened if Turner had not stopped? Could he and his cohorts have reached an arsenal in the nearby town of Jerusalem? What would history look like if his revolt had continued?

Round out the course with a look at President Kennedy’s assassination, an event that continues to inspire conspiracy theorists decades later. As Professor Jortner discusses, JFK almost didn’t make the trip to Dallas that ended in national tragedy. How would JFK’s survival have affected civil rights, the Cold War, and Vietnam? And how does asking counterfactuals help us understand the history that did happen?