Ever heard the phrase "Science progresses one funeral at time"? Who do you think coined that phrase? Hint: It wasn't trash collectors.
If scientists were really as open-minded and ego free as you claim, they wouldn't spend their lives defending work from their youth.
Scientists are people too. It's folly to imagine that scientists are less prone to bias and pride than non-scientists.
I think it's safe to say that virtually all major wars are caused by forces too powerful for one single person to make a difference.