Somebody eventually had to knit the whole world together. North and South. Eastern and Western Hemispheres. The person who launched that adventure was Christopher Columbus.

Critics will point out his many flaws. That the Native Americans didn't need discovering, having come across the Bering Straits millennia before. That, five centuries earlier, Leif Ericson slipped over to North America and established Vinland. And maybe Chinese explorer Zeng He sailed to North America around 1405.

But for global interconnection, the key was, as the phrase has it, "In 1492 Columbus sailed the ocean blue." Under sponsorship by monarchs Ferdinand and Isabella of Spain, the Nina, the Pinta and the Santa Maria began a new era of vast exploration of the world. The first two ships were small, only 50 to 70 feet from bow to stern. The flagship Santa Maria was larger, at 117 feet. The Spanish crew of 86 sailed for 35 days. Imagine going out into the vast unknown, with limited provisions on small ships.

Of course, Columbus originally intended to reach "the Indies," that is the Spice Islands in East Asia, when the Western Hemisphere got in the way. European sailors of that era were fascinated by the rich trading cities of Asia, which had been known from Marco Polo's travels. Then, as the History Channel described it, "With the men close to mutiny against their 'foreign' captain, Columbus was about to turn back when the cry went out at 2 a.m. on October 12 that land had been sighted."

Although a great sailor, Columbus proved to be a terrible political administrator of Hispaniola. And of course there's no forgetting the brutality came with the conquest of the Americas. But mature people can separate the flawed man from his achievements and can understand the historical magnitude of what his discovery unleashed.

As biographer Samuel Eliot Morison wrote, "We are right in so honoring him, because no other sailor had the persistence, the knowledge and the sheer guts to sail thousands of miles into the unknown ocean until he found land. This was the most spectacular and most far-reaching geographical discovery in recorded human history."

And as Felipe Fernandez-Armesto explained, "There had been many attempts to cross the Atlantic in central latitudes, but all -- as far as we know -- failed because the explorers clung to the zone of westerly winds in an attempt to secure a passage home. Columbus was the first to succeed precisely because he had the courage to sail with the wind at his back."

Columbus truly united the world