'How would western civilization be different if Christopher Columbus had not discovered America?' Many circumstances led to Christopher Columbus' discovery of America in 1492. He was born in the port city of Genoa, Italy. He learned the skills of seamanship from working on the sardine fishing fleets. It is also probable that his father owned his own coastal schooner used for trading wool. Head no formal education, which forced him to work in the field of sea navigation. In 1476, Columbus became a chart maker in Lisbon.
Any other career he may have chosen, could have prevented him from attempting to find a western sea route from Europe to Asia. America would be very different today, if not discovered by Christopher Columbus. I believe someone would have eventually discovered the new land, but much later. Western civilization would be less advanced today, if it had not been founded so long ago.
Settlers would not have had as long to develop colonies and establish trade with other countries. They would not have had as long to learn the skills of farming a new land. Civilization might be more primitive right now if it had not been discovered until a later time. If America had not been developed by settlers from other countries, the American Indians may have populated the land over time. They might have been the majority in America today.
They may have remained land owners and settled in colonies of their own. They may have rejected or fought off visitors from Europe, if they would have had more time to develop the western world. There is no way to know what western civilization would be now, without the discovery by Christopher Columbus. But it surely would not be what it is today!