What is Great Britain, after all? You could call it the non-existent national core of the state, the United Kingdom; or the alter ego of England as the unacknowledged heart of the UK state. Although the ‘national’ UK politicians make great capital out of Great Britain or Britain as the personality of the state, does Great Britain actually exist in the present in any fundamental national, political or constitutional sense? Great Britain is indeed the ‘foundation’ of the UK state because that state’s parliament was constituted as the parliament of the Kingdom of Great Britain through the Acts of Union between England [including Wales] and Scotland in 1707. When Ireland [later reduced to Northern Ireland] was added 100 years later to form the United Kingdom of Great Britain and Ireland, this was essentially an extension of the jurisdiction of the Great Britain parliament and government to include Ireland. So the UK, on this basis, remained Great Britain at its core.
The 1998 devolution legislation has changed the Union radically. The changes will be the permanent and most important achievement of the Blair government. However they have also unbalanced the Union to such a degree -by leaving England out of devolution altogether and by providing Wales with a mere fraction of what has been granted to Scotland- that unless balance is restored, the Union will come apart. The essence of a balanced Union is for each of the constituent parts to stand in the same relationship to the Union itself and to each other. That can be achieved in a very straightforward way by granting to both England and Wales their own parliaments with the same powers and executive as the Scottish Parliament, and the Union Parliament retaining the reserved powers it has now in relation to Scotland. The relationship of Scotland to the Union Parliament is the blueprint; and balance and justice can be easily achieved by extending it to England and Wales.
So Great Britain / Britain is just a ‘nation name’ or ‘national persona’ for the UK, not a formal nation in its own right. If you wanted to finesse this argument further, you could say that the reason why ‘Britain’ rather than ‘Great Britain’ tends to be used nowadays to evoke a national identity for the non-nation state of the UK is that ‘Great Britain’ refers back to the historical nation – ‘kingdom’ – of Great Britain about which people are vaguely aware that it ended when Ireland came on board; and that it is not, consequently, inclusive of Northern Ireland. So ‘Britain’ is used precisely because it is not the formal name of a state or a nation that does or does not exist in the present. Indeed, one might say that the power of the name ‘Britain’ to evoke feelings and ideas of nationhood is in inverse proportion to the actual existence, past or present, of such a state or nation.
Change has always happen and it will continue to happen, the question at the moment is will the Island be destroyed by federalism? I think not.