4 key turning points in Western history

[ThatOwlWoman]

According to Kenneth Harl, professor of history @ Tulane University, these are the four most important turning points in the history of western civilization:

1) Emergence of self-government (5th century BCE Greece).

2) Conversation of Europe to Christianity.

3) Discovery of the New World.

4) Industrial revolution.

Without the material wealth and relative political stability of America, I wonder how much longer the Industrial Revolution would have taken?