Richard, Clause 4 (of the British Labour Party) did originally call for common ownership though I think it was always understood to mean state ownership of industry (e.g. nationalisation, 1976 Industrial Common Ownership Act) rather than common ownership in the sense of the early socialists, such as the kind of society described in William Morris' News From Nowhere. That is, involving the abolition of money and associated activities (there is no need for a means of exchange with common ownership).

The concept of national identity is bound up with a class-based society, it is a divisive ideology in defense of the status quo. It is the idea that workers should identify with capitalists (the exploiting class) rather than fellow workers on the otherside of a political boundary. In socialism, there will be no need for the state, the organisation that has evolved to represent the interests of groups of capitalists against other groups and manage a social system where a minority of people own the means of living on which everyone depends. Common ownership negates the state and nation. Cultural identity is influenced by national identity but it is always a product of all the experiences and influences we come across. William Morris was always on about the possibilities of the decorative arts unrestrained by commerce, why not music too? (Whoops, even more digression!)