Realignment and Indeterminacy in the Two-Party State

At Least of All Evils, Dale Sheldon has begun a multi-part series of posts on the history and development of the two-party system in the United States. He begins from the premise that the status of the party system today is indeterminate:

Since the 1960s, political history in the US has been examined through a framework called the "party system", numbering periods of stability, separated by short spans of realignment. In other words, the times when the two parties at the forefront of American politics changed. There have been at least five such stable periods. There is debate to whether we are still in the fifth or are now in the sixth; or perhaps we are in an unstable realignment period.

Such indeterminacy in not confined to the United States. In a commentary for the UK's Independent from July, the leader of the Liberal Democratic Party, Nick Clegg, pronounced "an end to the duopoly that dominated 20th century Britain." Clegg writes:

The duopoly that dominated British politics in the 20th century is dying on its feet. In the 1951 General Election, only 2 per cent of voters chose a party other than Labour or the Conservatives. At the local elections last month, that figure had risen to nearly 40 per cent. The glue that held the duopoly together has disintegrated. Class divides have shifted. Geography no longer maps allegiance. Ideological differences once so important feel immaterial in the post-Cold War world. And because of globalisation and technology – not least the internet – identity has become more fluid and more complex.

People now define themselves in different ways. It's possible for individuals to find multiple homes in an ever-growing number of communities – real and cyber – where people are bound by their interests, principles and experiences, not just by geographical location. At the same time, in our increasingly atomised society, the traditional mass-membership parties no longer speak to people.

Sound familiar?