In simple terms, trade (the transfer of goods and services for money) is what makes Chicago so special. The reason for this is skillfully articulated in a book by Emily Lambert called, The Futures - The Rise of the Speculator and the Origins of the World’s Biggest Markets.
In the opening chapter of her book, Lambert describes the origins of Chicago:
“The place that became Chicago was founded on land known as Illinois Territory, named in a hat tip to the Native American groups that long inhabited the area. In 1808 the government built Fort Dearborn on a small hill above a river, near the shore of a large freshwater lake. The soldiers defended the fur trade. Chicago was built, literally, for trading.”
~ Chapter +0.01, Grain
Chicago is a hub for American and global business for many reasons.
Geographically, Chicago is important because it’s the largest midwestern city in the United States with direct access to the largest freshwater source in the Great Lakes.
Historically, Chicago has been a focal point for the region’s farmers to centralize the supply of the grain-based agriculture industry that feeds the world.
Intellectually, the Chicago School of Economics has produced some of the most prominent ideas in the fields of law, politics and economic theory that has shaped the global economy since its inception dating back to the late 1800’s.
Commercially, Chicago is home to the largest derivatives markets on the planet.
In my opinion, Chicago is the greatest culmination of trade theory and practice in the New World.