Falsification of history is normally associated with dictatorships rather than liberal democracies. Yet tendentious accounts of the recent past are part of the armoury of all types of political debate. Such manipulation usually has only a limited and short-term influence, because it is neutralised by different political parties offering contending versions of the past. But in some circumstances a particular political version of the recent past can harden into a one-sided form of history which obstructs the development of a more cogent or even an accurately-based historical understanding.