Bangkok Syndrome
In Thailand, one city holds most of the country’s universities, hospitals, financial institutions, major employers, government agencies, and the only major international airport. Bangkok, also serving as the country’s capital, has a population of 11.4 million people, a whopping 15% of the country’s population. The second largest city in Thailand, Hat Yai, has a measly 400,000 people. Bangkok has a gravitational pull that concentrates the nation’s resources, talents, and attention. There are no other centers of power, no other engines of opportunity. The rest of Thailand serves as a satellite to its darling capital. This malady is known as Bangkok Syndrome.
Many countries are afflicted with some form of Bangkok Syndrome, where one city (normally its capital) maintains an outsized population and power base when compared to the rest of the country. Very few countries have the geographic diversity of the U.S., where centers like NYC, L.A., and Silicon Valley, Chicago, D.C., and the Texas triangle balance one another out. In the UK, this city is London; in Norway, it’s Oslo; and in Costa Rica, it’s San José. To quantify this concentration, a measure called the Primacy Ratio was introduced by geographer Mark Jefferson. It’s calculated by dividing the population of a country’s largest city by that of its second-largest, indicating how unbalanced a country’s population is. In the UK, London is 4 times the size of Birmingham. Bangkok is 285 times larger than Hat Yai. This number helps reveal the geographic disparities woven into a nation’s social fabric.
The U.S. has quite a low Primacy Ratio (1.50), with large population centers on both coasts throughout the interior, distributing large pockets of opportunity across the country. Additionally, institutions like the Senate and the Electoral College function to (unjustly) dampen the power of population centers, further stifling the concentration of influence in a few cities. However, Primacy Ratios can be a useful metric for understanding geographic concentration and related relationships at the state level.
Using 2020 Census data for the population of different Metropolitan Statistical Areas, I calculated the Primacy Ratios for each state1, whose borders are obviously far harder to enforce, using a ratio of 2.3 as the cutoff for a ‘high’ primacy ratio. As the maps below show, the South and the Intermountain West tend to have quite low primacy ratios, while the Northeast, the Rust Belt, the Sunbelt, and the Pacific Northwest all have high ratios. States with ratios above 6.5 include Washington, Maryland, Georgia, Minnesota, New York, and Illinois, with the highest ratio of all (25.81).
Analysis
My first point of interest after assembling this data was to see if there was any relationship with rural populations or state-level out-migration. For low PR states, the average net migration rate between 2020 and 2024 was 6.22 per 1,000 residents. For high PR states, it’s 2.97, and for very high PR states its -15.32. While this does point to a trend, geography may play more of a role than anything else. Low PR states are concentrated in the South and the Intermountain West, regions that, due to climate and cost of living, are experiencing a population boom. Since high and very high PR states are concentrated in the Northeast, where the cost of living is high, I can see that having a larger influence on these trends. However, it’s also possible that the concentration of opportunity in a few expensive cities is a root cause of the state’s high cost of living (though, given Chicago’s and Minneapolis’ relative affordability compared to NYC, I’d hazard to say these trends are fairly loosely associated).
Regarding the rural population, it seems that having a high primacy ratio is associated with growing rural populations. Between 2020 and 2023, rural populations in low PR states grew by 2.9 per 1,000 residents, whereas high and very high PR states grew by 3 and 3.5 per 1,000 residents, respectively. Again, it’s difficult to decouple these from geographically specific trends. For example, one reason for this growth could be that folks in more expensive, concentrated urban areas were more likely to move to the countryside during the COVID shift to remote work. Alternatively, it’s possible that having one superstar city in a state has some sort of positive effect on rural economies in a way that more diffuse urban areas do not.
Moving to a more qualitative outlook, these primacy ratios can be useful proxies for understanding urban-rural conflicts in different states. Take my current state of residence, Missouri, which has a low primacy ratio. At the far ends of the state are St. Louis and Kansas City, each roughly the same size, and between them are several sizable urban areas, including Columbia-Jefferson City, Joplin, and Springfield. The capital isn’t located in either of the two metropoles. While there’s still animosity between the two large cities and the less populated parts of the state, it’s not particularly intense and strikes me as more about partisan fights or (often unfounded) fears of crime rather than resentment of the cities themselves. Rural Missourians may view our cities as shitholes, yes, but not as their enemy. Texas and Iowa have similar situations, with urban areas of similar caliber being distributed around the state, allowing for opportunities and amenities to be accessible to residents in the nearby countryside. While you may hear some griping about Des Moines from folks in Emmet or Keokuk counties, Iowegians don’t outright revile their focal city quite like Illinoisans do with Chicago. They don’t have to drive into the capital for medical care, education, or to the airport. By having sizable cities around the state, resources are more available within a reasonable drive.
Which brings me to the prairie state, the state with the highest ratio of the 50 states. The weight Chicago and its assemblage of suburbs has on the state is difficult to overstate. Aside from the state capital in Springfield and the University of Illinois’ flagship campus in Urbana-Champaign, the state’s financial, media, and service industries are all concentrated in Chicagoland. Having met folks from other parts of Illinois, such as Carbondale or rural DeWitt County, folks outright despise Chicago and the city’s gravitational pull.
This dynamic is present in other states like Washington, New York, and Minnesota, with a sizable plurality of rural residents outright despising the citizens of Seattle, NYC, and Minneapolis-St. Paul. If your entire state’s media apparatus, government, and business community is heavily concentrated in one city, the resulting resentment can come to define one’s rural identity. Instead of being rooted in place, it comes to be defined as opposition to the local metros. I’ve seen it happen, where dignified pride in one’s local landscape, people, and industry slowly gives way to flat bitterness. Having one city to concentrate this ire on intensifies the emotional rot.
Years ago, I watched a very interesting TED Talk2 titled How megacities are changing the map of the world. The upshot of the talk is that, as metropolises such as the Pearl River Delta or the Northeast Corridor begin accumulating populations and economic fortunes that eclipse whole nations, connectivity (improved communications, ease of travel, and capital flows) between cities will become the most important geopolitical project of the future.3 The quote that stood out to me was “In a megacity world, countries can be suburbs of cities.” Imagine the insecurity engendered for those cast in the shadows of these burgeoning megacities.
For states with a lopsided urban-rural population distribution, the economic and social challenges such imbalances cause can seem intractable. However, I’m hopeful that with policies and efforts to connect urban and rural economies and societies into clusters that drive regional prosperity, we can begin mending the rural/urban divide in this country. But before such approaches can be implemented, we need metrics to document the presence and intensity of such divides across the country. I believe the Primacy Ratio is a useful tool for beginning to understand the geographic forces underlying polarization.
What I’m Reading, Watching, and Listening to
CSA boxes get people buying fresh from farms, but will customer convenience hurt the mission?: In an era of high consumer convenience in the marketplace, community-supported farms are learning to navigate the challenges those expectations bring.
Project examines what ‘thriving ag’ could look like in future: A good piece of further reading, this article summarizes some recent research exploring how farmers can co-exist with housing developments as urban areas continue to sprawl. This includes what conservation practices assuage resident concerns regarding pollution and some counterintuitive findings about how urbanites view local food.
Zero-Waste, Except for the Strip Steak: A small restaurateur discussing her strategies for running a zero-waste restaurant, and how such efforts must consider the supply chain before the delivery truck rolls up.
Methodological note for the real nerds: There were three approaches I could use to calculate this number: the population of the largest cities themselves and the population of the largest MSA’s, either including or excluding MSA’s that are primarily in border states. Each of these can provide useful context and have their benefits and drawbacks, but I decided to exclude predominantly out-of-state MSAs since my focus is on the internal dynamics of different states. I do find it interesting how the porousness of state borders influences how these numbers can be calculated and used when compared to using similar metrics on a national scale.
Back when TED Talks were actually insightful.
While a bit dated given current geopolitical unravelings, the fact still remains that urbanization continues to accelerate and economies are still global. The broad framework still seems sound, even if an ‘end of history’ energy remains.