very simple and obvious explanation for the differences between the two halves of Nogales that you’ve probably long since guessed: the very border that defines the two halves. Nogales, Arizona, is in the United States. Its inhabitants have access to the economic institutions of the United States, which enable them to choose their occupations freely, acquire schooling and skills, and encourage their employers to invest in the best technology, which leads to higher wages for them. They also have access to political institutions that allow them to take part in the democratic process, to elect their representatives, and replace them if they misbehave. In consequence, politicians provide the basic services (ranging from public health to roads to law and order) that the citizens demand. Those of Nogales, Sonora, are not so lucky. They live in a different world shaped by different institutions. These different institutions create very disparate incentives for the inhabitants of the two Nogaleses and for the entrepreneurs and businesses willing to invest there. These incentives created by the different institutions of the Nogaleses and the countries in which they are situated are the main reason for the differences in economic prosperity on the two sides of the border.
Why are the institutions of the United States so much more conducive to economic success than those of Mexico or, for that matter, the rest of Latin America? The answer to this question lies in the way the different societies formed during the early colonial period. An institutional divergence took place then, with implications lasting into the present day. To understand this divergence we must begin right at the foundation of the colonies in North and Latin America.
THE FOUNDING OF BUENOS AIRES
Early in 1516 the Spanish navigator Juan Díaz de Solís sailed into a wide estuary on the Eastern Seaboard of South America. Wading ashore, de Solís claimed the land for Spain, naming the river the Río de la Plata, “River of Silver,” since the local people possessed silver. The indigenous peoples on either side of the estuary—the Charrúas in what is now Uruguay, and the Querandí on the plains that were to be known as the Pampas in modern Argentina—regarded the newcomers with hostility. These locals were hunter-gatherers who lived in small groups without strong centralized political authorities. Indeed it was such a band of Charrúas who clubbed de Solís to death as he explored the new domains he had attemped to occupy for Spain.
In 1534 the Spanish, still optimistic, sent out a first mission of settlers from Spain under the leadership of Pedro de Mendoza. They founded a town on the site of Buenos Aires in the same year. It should have been an ideal place for Europeans. Buenos Aires, literally meaning “good airs,” had a hospitable, temperate climate. Yet the first stay of the Spaniards there was short lived. They were not after good airs, but resources to extract and labor to coerce. The Charrúas and the Querandí were not obliging, however. They refused to provide food to the Spaniards, and refused to work when caught. They attacked the new settlement with their bows and arrows. The Spaniards grew hungry, since they had not anticipated having to provide food for themselves. Buenos Aires was not what they had dreamed of. The local people could not be forced into providing labor. The area had no silver or gold to exploit, and the silver that de Solís found had actually come all the way from the Inca state in the Andes, far to the west.
The Spaniards, while trying to survive, started sending out expeditions to find a new place that would offer greater riches and populations easier to coerce. In 1537 one of these expeditions, under the leadership of Juan de Ayolas, penetrated up the Paraná River, searching for a route to the Incas. On its way, it made contact with the Guaraní, a sedentary people with an agricultural economy based on maize and cassava. De Ayolas immediately realized that the Guaraní were a completely different proposition from the Charrúas and the Querandí. After a brief conflict, the Spanish overcame Guaraní resistance and founded a town, Nuestra Señora de Santa María de la Asunción, which remains the capital of Paraguay today. The conquistadors married the Guaraní princesses and quickly set themselves up as a new aristocracy. They adapted the existing systems of forced labor and tribute of the Guaraní, with themselves at the helm. This was the kind of colony they wanted to set up, and within four years