Well, gee, sailor, why don’t you point out what I’m ignorant about? I’ll post points, and you refute them, m’kay? If you can’t do that, maybe you can find something else constructive to add. Or maybe not.
1. He was wrong about the size of the Earth.
This was Columbus’ whole argument. He argued that the Earth was much smaller than it was thought to be; so much smaller, in fact, that China and India must be juuuuuust on the other side of that big ocean to the west of Spain. Advisors told him the Earth was bigger than he thought, and he refused to believe them. He used a circumference of around 15,000 miles for his plans, which is about 10,000 miles short. Miscalculating your travel distance by nearly 50% qualifes one for bumbler status quite easily.
2. He was wrong about where he thought he was going.
See above. Columbus assumed that the Earth was small, and that Asia was on the other side of the Atlantic. Had it not been for the intervening continent and island, Columbus and his three ships would have been lost at sea, since they didn’t carry provisions for a trip that long. When Columbus reached the Sargasso, he was befuddled by the fact that there were so many birds around, since he expected there to be no land yet. (He was on his way to Asia, remember?)
3. He was wrong about where he ended up.
Columbus assumed he was in Asia, or the subcontinent. Nope, sorry–he was in the Caribbean. Not only that, but he wrongly claimed the prize that was to be awarded by the Spanish Crown to the sailor who first sighted land.
4. He had no qualms about eliminating native populations to take their stuff.
His first day in the New World, Columbus and his men captured six natives to use as servants. His third day there, he wrote in his log that “with 50 men you could subject every one and make them do what you wished.” He spent most of October and November, 1492, doing two things: looking for gold and capturing slaves. The only reason that the Spaniards did enslave the entire Caribbean population was that they made poor slaves–they tended to die on the voyage to Spain.
Columbus started unfounded stories that the inhabitants of the islands were savages and cannibals, so that when the Spaniards returned in 1493, they launched a vicious, full-scale invasion force. Columbus himself took captured female islanders and basically gave them away as concubines to his men.
For details on much of this, see http://www.halcyon.com/wfrazier/columbus.htm.
OK, sailor, your turn. Show me how ignorant I am.