WHATEVER the question, devo max is not the answer. This old canard has been resurrected of late, both by mischievous nationalists looking for a rise and by a range of Labour folk who, frankly, should know better. It needs buried, for once and for all.

Devo max means the devolution of all powers from Westminster to Holyrood other than those which are essential characteristics of a state, and which only a state could exercise. In short, this means everything being devolved except defence and foreign policy, the currency and monetary policy.

In particular, it means that all fiscal powers would be devolved – all taxes raised in Scotland would go to the Scottish Government and none would go to Westminster. Sometimes known as “full fiscal autonomy”, devo max would mean that Scotland was fully responsible for raising all of the money it spends.

Already you can see the inherent contradiction: Scotland would have its defence and foreign policy, its currency and its monetary policy paid for by someone else. Making no fiscal contribution to the British exchequer, it would none the less continue to benefit from British protection and security, diplomatically, militarily, and in terms of the currency.

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To overcome this problem, Alex Salmond once suggested that, in a cute reversal of 300 years of practice, Scotland could transfer a block grant to HM Treasury in Whitehall. Mr Salmond knew, I’m sure, that no country in the world operates like this. His was a recipe not for the rebuilding of the UK state, but for its destruction. And why should it not be? He and his parties have devoted their entire working lives to this cause.

Devo max would destabilise the United Kingdom to such a degree it would end the United Kingdom. That’s fine if you are a nationalist hellbent on independence. But let us understand what this means. Devo max is not and can never be an alternative to independence: it is a route to independence. If your question, therefore, is what is the best alternative to independence, devo max is not the answer.

That might not be your question, of course. Instead, you might ask: what is in Scotland’s and/or Britain’s best interests? You might be committed to the United Kingdom in principle, yet none the less of the view that the United Kingdom needs to change in order to survive – that the Union, in its current iteration, may not endure.

If this is your position, great. But, again, devo max is not the answer you are looking for. We need to be honest about this: devolution has its limits. It can go so far, but only so far. You cannot salami slice the state, handing more and more of its powers away, forever – at least, you cannot do that without in the end making what is left of the state so weak it is not capable of being preserved.

States need to control their borders. This rules out the full devolution of migration policy. States need to control the terms on which they trade. This rules out the full devolution of policy as regards goods and services. States need to preserve themselves not only as political units, but in terms also of economic and social cohesion. The United Kingdom is a social union as well as a political one. This is why we have a single, UK-wide, state pension. It is why we have a single, UK-wide regime of employment rights (including a single national minimum wage). And so on.

None of this means there can be no more devolution to Scotland but it does, if we are honest, mean there really is not much left in Westminster’s hands which can sensibly be devolved without fatally undermining the integrity of the state.

In terms of the current settlement there are two areas I would look at: borrowing powers and modest powers over migrant labour. But I would look at these not because I imagine for a moment that further devolution in these areas will persuade Yessers not to support independence any longer. I would look at them because, in my judgment, recent experience has shown that the current settlement does not have them quite right, and it would be in the public interest for adjustments to be made.

Devo max, or full fiscal autonomy, is a chimera. There is no state anywhere in the world with multi-layered government (as we have in the UK) where the centre does not make a substantial fiscal transfer to the nations or regions. The Canadian Provinces, the German Länder, the Swiss Cantons, the American and the Australian States – in every single one of these cases there is a transfer from the centre. Full fiscal autonomy within a larger state is a myth, a mirage, a creature of Alex Salmond’s over-fevered imagination.

We don’t need to create anew a fresh alternative to independence: we already have one. It’s called union. I’m all in favour of a flexible union, of a union that understands it cannot stand still but must move with the times. By all means let us look afresh at instances where in its current form or structure it is not working. This year’s renegotiation of the fiscal framework (which will require reconsideration of borrowing powers) is an opportunity.

But let us hear no more nonsense about devo max. In the end, there is no third way, no middle of the road alternative between the two options Scotland faces. Devolution within the United Kingdom or independence from the United Kingdom are our only constitutional options.

To my mind we chose well in 2014 and there is no reason to revisit the wisdom of that choice. Others may disagree. So be it, but let’s not muddy the waters by pretending we can add other options to the mix. We cannot.

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