I'm trying to find a book I read decades ago in which a group of people discover that for years the government has been going back into the past and arranging that certain events--and specifically, people--do happen. For example, I believe in "reality" Adolf Hitler died well before reaching adulthood; similarly Gengis Khan. In the "present" that the government has created, they and others grow to adulthood and wreak the havoc that we now know to be fact. As a by-product, life is tougher, harder and people more belligerent than they would otherwise have been. The group succeeds in overthrowing the government and reversing the process…the rest of the story I'll not reveal. Ideas anyone?