We learn from history but have to understand that it is not the absolute determining factor that controls our behavior in the present.
Of course not, but the study of history can provide immense insight to current affairs. Simply do a search in the Sunday London Times on August 2, 1920 for a letter by Col. T. E. Lawrence to see what I mean. History has a habit of repeating itself, so by studying the mistakes of the past, we may be able to avoid similar ones in the future.

I would further comment that history has been distorted many times in order to provide excuses for what I can only refer to as evil behavior and there were a whole lot of people who thought that the distorted version was the absolute truth...did that excuse their actions or inactions? It's Rashomon....there is no one absolutely objective correct opinion on what actually happened and once an event is over, all we have is opinions.
My only response is, though, that there are objective historians who do try to see both sides of history and present as accurate and objective view of history as possible -- and yes, history is only as accurate and objective as the people who write it -- but that is no reason to simply dismiss history as simply "opinions". That is trivializing the work of many good scholars who attempt to present the most accurate perspective of a historical person, event, place, etc.

T.