There is no consensus even today on the merits of Napoleon - and certainly no agreement on the rights and wrongs of the origins of the First World War.

There are thus great swathes of the past where understanding is more important and reputable than judgement, because the principal actors performed in line with the ideas and values of that time, not of ours.

Diplomacy is unfashionable in the world of knee-jerk reaction and the dogmatic sound bite on television.

Men like Hitler and Stalin and their immediate lieutenants cannot plead in defence of their actions that these were justified by the accepted values of that time.

It is normal for politicians in all countries to profess themselves the pupils of history, anxious to draw the right lessons from her teaching.

Margaret Thatcher was fearful of German unification because she believed that this would bring an immediate and formidable increase of economic strength to a Germany which was already the strongest economic partner in Europe.

Ten Downing Street is a house, not an office. That is its most important characteristic.