19 20 21

In AD 1000, the largest city in the world was Cordova, Spain, pop. 450,000; No. 2 was Kaifeng, China: 400,000. This according to 192021.org.

More from 192021:
AD 1500 - No. 1: Beijing, China, pop. 672,000; No. 2: Vijayanagar, India, pop. 500,000.
AD 1800 - No. 1: Beijing, pop 1.1MM; No. 2: London, UK, pop. 861,000.
AD 1900 - No. 1: London, pop. 6.48MM (what an increase!); No. 2: New York City, NY, pop. 4.24MM.
AD 1950 - No. 1: New York City, pop. 12.46MM; London, 8.86MM.
AD 2005 - No. 1: Tokyo, Japan, pop. 35.19MM; No. 2: Mexico City, Mexico, pop. 19.40MM.

Doesn't California have 35MM people? And Tokyo has the same population? I lived in Tokyo in the early 1980s. I was born and raised in California. Didn't realize I was one caput or capitulum in roughly the same population, just different density per square mile.

The premise of 192021.org is that currently half of the world population lives in cities -- big cities. Thus, increasing the world is increasingly seen, not as a group of countries/nations, but rather as a network of major cities. The claim is that by 2050, it is expected that 66% of world population will live in cities. The flight from rural to urban that began in the United States during the industrial revolution, has gained momentum across other continents.

According to Wikipedia, the 20th largest cities are... Mind boggling.

And here I am writing this in a rural county in a city of about 28,000 people, that is part of a state which is united by a federal government.

Will the day come when the economic and social intercourse between mega-cities trump my value or import as a citizen of a sovereign nation? Interaction and interdependency already slant the policies and actions of presidents and prime ministers. Being practical, expedient, strategic.

In the U.S., a contender for the presidency runs solely on the basis of two facts: (1) he was mayor of one of the world's mega-cities and (2) he was mayor of the same city on 9/11.