Splitting up the United Kingdom isn't all that hard to do: Lord Smith's proposed Devo Max settlement is grossly unfair for English voters (photo: Jeff J. Mitchell/Getty Images)

The Scottish referendum result in September has well and truly pushed Humpty Dumpty off the constitutional wall, where he has been precariously perched since the Scotland Act of 1998. And, as in that nursery rhyme, there is no prospect of putting Humpty Dumpty back together again in any recognisable form. So where next with the various pieces that lie strewn across the political battleground?

Tam Dalyell was the MP who saw how devolution had the potential to destroy the British Constitution as we know it. He posed a simple but deadly question: how could it be fair to English voters that their MPs are excluded from having a say in what happens to the constituents of Scottish MPs, whereas Scottish MPs can vote on all English matters? Worse still, those Scottish and sometimes Scottish Nationalist MPs, could now be in a position to put into power at Westminster a government that did not have a majority among English MPs.

Tam is still waiting for an answer to that question he posed back in 1977, which is now known as the West Lothian Question. During a recent interview he suggested that one response to the referendum result should be the abolition of the Scottish Parliament, to batten down the hatches, and wait for the inevitable political hurricane that will result to blow itself out. Tam's preferred option, as he well knows, isn't going to happen. The genie of country-based nationalism is well and truly out of the bottle and not only in Scotland. The only durable response, therefore, is to see the devolution principle through to its logical conclusion, which means a proper and durable settlement for England.

That is not what the Prime Minister is offering. The Smith Commission — established as the votes were counted in the referendum — reported in November on a "Devo Max" settlement. It continues the political muddle that has existed since the original Scottish Devolution Act and a muddle that advantages Scotland but leaves England with the most inferior political status of any of the countries that make up the UK. The report's 21 major fiscal and constitutional reforms can be grouped around two major themes.

Scotland will set the rates of income tax and will keep half of the existing VAT revenue raised in Scotland. Scotland will likewise have the power to borrow in its own right in the international money markets. A great silence falls on how the revenue from these tax-raising powers will be offset against the Barnett formula that decides the amount of central taxpayer support to each of the four constituent countries of the United Kingdom.

As well as these major fiscal advantages Scotland becomes sovereign over how it runs its own elections. From now on, we will almost certainly have no common suffrage. Scotland will be allowed to determine, for example, its own qualification for the age at which citizens first vote. This reform is presented in the Smith Commission as though it were little more than a bauble to decorate a constitutional Christmas tree. But a moment's thought suggests how destructive it will be to an equality of votes throughout the United Kingdom. For the first time since universal suffrage there will be no universally geographically applied qualification for the vote.

The Smith Commission report is the latest instalment of an appeasement policy that has been operated in Scotland's favour for the past 40 years or more. The cost of the appeasement has been borne exclusively by England.