In the precolonial times South America and Central America were, in fact, considerably more developed than most of North America, including large, complex architectural structures, more intenstive argriculture and animal husbandry, more developed mathematics and mercantile practices, et cetera. Only in Mexico did there exist native cultures that were even comperable to those in the South.
The discovery and subsequent subjugation (and in many cases, genocide) of the native cultures by the Spanish conquistadors (shortly followed by the Portuguese, French, and English) virtually wiped the slate clean, displacing them with their own established cultures. The Europeans had, among other faculties, a resistance to a multitude of malignant diseases, the knowledge and practice of military operations and combined arms tactics, gunpowder and cannon, sailpower (by which to move troops and strike from sea without exposure to return fire), iron tools and cotton/linen textiles, et cetera. (See O’Neill’s Plagues and Peoples as a good introduction to why the Europeans, in general, came to dominate the Americas so easily.)
So the Europeans established themselves in the Americas by the same traditions and cultural mores they practiced in Europe. For the Spanish, this was perpetuating a bloated bureaucracy largely dominated by the Jesuit order across the southern part of North America and points south. For the still Catholic but more liberal French and the Protestant and Angelican English, more focus was given to commerce than brute pilage (and it probably helped that while the South American natives tended to have large reserves of gold and silver to steal, the North Americans were never so wealthy.)
So, while the Spanish (and Portugeuse) were getting fat, dumb, and brutal, the French and English were engaging more in sustainable exploitation (fur trapping, agriculture, exploration of manufacturing metals and materials). The eventual scism of the American colonists from their European powers eliminated the one-way drain of the enormous resources of this continent, and the geographical barrier (the Atlantic Ocean) prevented the Americans from having to utilize proportionally equivilent resources to defend from challengers, whereas the Europeans (with their relatively permeable borders) were constantly engaged in fighting and defense. Along with eliminating tribute to the traditional monarchies of Europe the North Americans also eliminated the monarcy, replacing it with a small and fairly efficient representative government which encouraged commerce, land trading and development without the kind of class strictures found in Europe.
The South Americans, meanwhile, were still laboring under the increasingly bloated and inefficient thumb of the Spanish and the Jesuits, who discouraged development and provided little in the way of encouragement, education, or commerce other than what was necessary to reinforce the authority of the Church and keep the gold flowing back to Spain. When that cow ran dry (and the Spanish were reduced to a second rate military and political influence in European affairs) South America suffered a similar decline.
There are other factors as well–the difference in amount of arable land between the two continents, the east-west alignment of North America along a temperate zone and the relatively accessibly geography as opposed to South America’s north-south alignment and significant mountainous barriers to travel between coasts, the relative ease of water transportation in the North as opposed to the few and hazardous rivers in the South, et cetera–but I think the most significant initial influence was the difference between the cultures and their differing goals and methods in colonization.
South America still has great natural resources, and nations like Brazil and Argentina have, if they can get their act together politically and economically, the potential to become economic competitors in the world marketplace, but they stand significantly behind the rest of the industrial world in terms of development.
There’s no saying that we can’t regress to the same point, though. Today a king; tomorrow a pauper. The cold laws of economic game theory bow down to no majesty.
Stranger