Possible to judge history objectively?

The other day, I watched ‘Churchill’s darkest decision’ on 4oD which I enjoyed very much as it made me think about dilemmas we face, small and big throughout our lives. While discussing the programme, we start talking about ‘mistakes’ that Churchill have made in WW2. ‘Mistakes’…then we began to think about judgements that we make about the past, especially other people’s past. We are not hesitant to make judgement but what are these judgements based on? In Churchill’s WW2 case, we may have access to vast amount of documents and first and second hand experience accounts, is this enough for us to make a judgement about what was a right and wrong decision etc. Some may claim that it is being objective and analysing data should provide a neutral perspective, ‘well, data says so’ argument. I begin to have a problem of whether we are being too ‘objective’. Shouldn’t we be subjective to be able to make an objective judgement? But then again, we could never be subjective to other people’s past which means, it seems to me that we can never make a judgement of other people’s past and claim that it is objective. Can there ever be an objective view point?