Two and a half centuries have passed since the United States formally severed political ties with Great Britain to declare its independence. In that time, the young, scattered collection of Atlantic coastal settlements has evolved beyond all recognition into a transcontinental global superpower, but the core cultural and political fractures that marked its earliest days remain embedded in the fabric of modern American life, reshaping contemporary politics from immigration policy to territorial ambition.
When the first 13 colonies secured independence, their combined territory stretched across just 430,000 square miles (1.1 million square kilometers). Today, that geographic footprint has expanded eightfold to roughly 3.7 million square miles. Population growth has followed an even more staggering trajectory: the 1790 national census counted just 4 million residents (including enslaved people), while the 2025 population estimate puts the total at 343 million – an 8,475% increase over two centuries.
Even as the nation’s physical and demographic size have exploded, historians trace modern political fault lines directly to the cultural identities that formed in the nation’s earliest years, a split that continues to define the presidency of Donald Trump. Key pledges of his agenda – from strict curbs on immigration to renewed calls for territorial expansion – echo the divisions that existed from the founding era, when heated disagreements over slavery, constitutional governance, and economic systems left the new nation deeply fractured. As Boston College history professor and prominent Substack author Heather Cox Richardson notes, 18th century observers widely predicted the fragile new experiment would collapse on its own: “All we need to do is stay over here and wait till they tear themselves apart and go back and pick them up,” she summarizes the contemporary perspective.
Colin Woodard, director of the Nationhood Lab at Salve Regina University, maps these early divides into distinct regional identities that still shape American politics today. The first, what Woodard terms “Yankeeland” across the northern U.S., traces its roots to Puritan settlers fleeing religious persecution in Europe, later reinforced by German and Scandinavian arrivals who cemented a pluralistic cultural outlook. In contrast, the broad mid-continental band of Greater Appalachia was first settled by independent-minded Scots-Irish migrants, whose experience of English oppression left them deeply suspicious of centralized state power. “For them, freedom means maximising the autonomy and freedom of the individual and any growth in the power of government axiomatically means individuals are less free,” Woodard explains, a philosophy directly opposed to Yankee New England’s more communitarian outlook. Further south, the Deep South developed into an oligarchic, hierarchical society built around a landowning elite, many of whom brought the system of chattel slavery with them from Caribbean plantations.
The young nation nearly doubled in size overnight with the 1803 Louisiana Purchase from France, and by the 1820s, territorial expansion had pushed the U.S. border all the way to the Pacific Coast via the Oregon Country acquisition. This westward push was ideologically fueled by the doctrine of “Manifest Destiny,” the widespread belief that the U.S. was divinely ordained to expand across the entire North American continent and beyond. This expansion brought competing regional cultures into new conflict: the harsh interior West mirrored Appalachia’s rugged wilderness and attracted similarly individualist settlers, while the Pacific Coast became a battleground between those values and the commercial, more government-friendly culture of transplants from the Northeast.
These same divides are clearly visible on today’s presidential electoral map. The U.S. Northeast and West Coast remain strongholds of liberal politics, broadly supportive of expanded government involvement in social and economic life, while the South, stretching from Texas to Florida, and the interior West have become the backbone of modern Republican conservatism.
By the end of the 19th century, large-scale territorial expansion had come to a halt, but demographic growth continued to accelerate, driven almost entirely by successive waves of immigration. “One of the things that really is at the center of the United States of America is immigration,” Richardson says. “The one thing that does link us all is that concept that we can make a future that we want.”
The first major immigration wave ran from the 1840s to 1889, bringing 14 million primarily northern and western European arrivals to U.S. shores. A second wave from 1890 to the 1920s brought more than 18 million migrants from southern and eastern Europe, and each new influx sparked a fierce nativist backlash, as established residents worried new arrivals would undercut wages and erode existing cultural norms. Restrictive policies soon followed: the 1882 Chinese Exclusion Act barred all immigration from China, and the 1924 Immigration Act imposed strict national origin quotas that cut overall immigration dramatically enough to create a clear, lasting dip in annual U.S. population growth.
It was not until the 1960s that these restrictive quotas were lifted, opening the door to the current immigration wave that has reshaped American demography. Since that reform, more than 70 million new immigrants have settled in the U.S., the vast majority from Asia and Latin America, including roughly 18 million from Mexico alone. Data from the Migration Policy Institute shows that by 2024, foreign-born residents made up 14.8% of the U.S. population, matching the all-time historical peak set in 1890, and immigration accounts for 84% of all current U.S. population growth.
Historically, early 19th and 20th century immigration waves – driven by industrial expansion in the northern states – shifted national political power toward the North. This geographic imbalance intensified sectional tensions: Southern political leaders pushed for continued territorial expansion to add new slave-holding states and maintain their national influence, a conflict that ultimately led to Southern secession and the American Civil War.
Modern demographic shifts have reversed this historical pattern. Today, large numbers of immigrants and transplants from northern states are relocating to the South, drawn by booming urban economies in Texas and Florida. At the same time, the ongoing crisis of unauthorized migration across the U.S. southern border has stoked widespread cultural and political anxiety, creating the conditions for the resurgence of populist conservatism embodied by Donald Trump’s second presidency.
Since returning to the White House, Trump has moved quickly to fulfill his campaign promise of mass deportations of undocumented migrants. He has also openly embraced a nostalgia for 19th century territorial expansion, floating proposals to acquire Greenland, repatriate control of the Panama Canal from Panama, and even annex Canada and Venezuela as new U.S. states. This agenda marks a sharp reversal of the last century of American history: for 150 years after the end of continental expansion, the U.S. shifted focus from growing its territory to gradually opening its borders to broader immigration. Today, Trump has flipped this script, prioritizing new territorial gains while sharply restricting entry to new arrivals.
Trump and his supporters argue that mass immigration threatens to permanently alter the fundamental character of the American nation, with the former president frequently warning, “We won’t have a country anymore” if current policies continue. Woodard argues this anxiety is not a new, modern phenomenon – it is the latest iteration of a 250-year-old core debate over what it means to be American. “That does not come out of nowhere,” he says. “We have the meta struggle in American history: Are we a civic nation devoted to … a society where every individual human can be equally, universally and sustainably free over time? Or is this a state that belongs to a certain group of people that are the real Americans by blood and descent?”
In the scope of human history, 250 years is a fleeting moment, barely a blip on the timeline of global civilizations. But for the United States, two and a half centuries have brought transformation unlike almost any other nation on Earth. Even so, the deep-rooted divisions at the nation’s core and the persistent anxiety over its future have remained a constant through every era of growth and change.