Bruce, Chernobyl happened in 1986 and Fukushima in 2011. There have been another 9 serious accidents. If the world had been using nuclear power everywhere for the last 50 years it'd need something like 15,000 plants, there'd be a serious accident every month, and we'd have run out of mined uranium in about 5 years.
Why nuclear power will never supply the world's energy needs
On the other hand, if the world had started rolling out large-scale renewable plants 50 years ago, imagine how fast the innovations in wind, solar, hydro, batteries, and collection & storage in general would have occurred.
As to what would never have happened - Exxon Valdez, Deepwater Horizon, Gulf War to name a few.
But a few billionaires would not be billionaires if we'd gone that way.