Explain the concept of Manifest Destiny and describe the Oregon Trail migration and the 1846 Oregon Treaty as examples of it in action.
In 1845, a newspaper editor named John L. O'Sullivan gave a name to an idea that was already spreading fast: Manifest Destiny, the belief that the United States was destined, even divinely justified, to expand across the entire North American continent. The idea offered a sweeping, confident justification for taking land, but it rarely asked what that expansion would cost the people -- Native nations, Mexican citizens -- already living on that land.
Manifest Destiny was not just an idea on paper; it moved real families west. Starting in the early 1840s, tens of thousands of American settlers packed covered wagons and traveled the roughly 2,000-mile Oregon Trail from Missouri to Oregon Country, a journey that took four to six grueling months and carried real dangers -- disease, river crossings, and hardship along the way. Oregon Country was jointly claimed by the United States and Britain, and expansionists demanded the U.S. take all of it up to the line of 54 degrees 40 minutes, chanting "Fifty-Four Forty or Fight!" Rather than risk a war, the two countries negotiated the Oregon Treaty of 1846, splitting the territory at the 49th parallel -- the border that Washington and Oregon still share with Canada today.
Mastery looks like: They can define Manifest Destiny in their own words and describe both the Oregon Trail migration and the 1846 Oregon Treaty as concrete examples of the idea in action.
Common stumbles: Treating Manifest Destiny only as a harmless can-do attitude without noticing what -- and whose land -- that expansion actually required.