History is useful when it is used properly: to understand why we and those we must deal with think and react in certain ways. It can offer examples to inform our decisions and guesses about the consequences of our actions. But we should be wary of looking to history for dogmatic lessons.We should distrust those who abuse history when they call on it to justify unreasonable claims to land, for example, or restitution. MacMillan illustrates how dangerous history can be in the hands of nationalistic or religious or ethnic leaders who use it to foster a sense of grievance and a desire for revenge.