The New Year has seen great disturbance in the Force. A call for d*vo m*x to be added to the ballot paper of the Scottish independence referendum has provoked outrage from the guardians of nationalist purity. Well, it makes a change from the row over whether women can have penises, which has preoccupied the SNP Twittersphere for the last two years.

The former SNP policy chief Chris Hanlon didn’t actually say he supported home rule. Heaven forfend. Only that he thought it might make sense for the hypothetical Indyref2 ballot paper to include the constitutional solution supported by most voters. “The people,” he said, “must have the option of choosing the path the largest percentage of them favour.”

“Idiotic, foolish, nonsensical” barked the SNP minister Kevin Stewart. “A con” claimed a chorus of nationalists online. Our sister paper The National has been a riot all week as SNP luminaries have lined up to trash the deviant maxers, ensuring, in the process that the idea gets max exposure.

“No-one is talking about devo max” say the SNP leadership, when of course everyone is. And have been for some time. As this column pointed out last year, a constellation of figures on the nationalist fringe, ranging from the former SNP justice secretary Kenny MacAskill to the independence-friendly academic, Professor Jim Mitchell, and the ex-Labour MEP David Martin of the Scottish Citizens’ Assembly, have been ruminating about maximum devolution all year. So have many in the SNP who don’t admit it.

The reasons are fairly obvious. Politics, like nature, abhors a vacuum and since nothing of substance has emerged from the SNP leadership on the constitution for five years, it is inevitable that others would try to fill in the Indyref gap. Even the SNP’s landslide victory in the Scottish Parliamentary elections last year, which led many in the metropolitan chattering classes to assume independence was nigh, provoked a nothing response from the First Minister.

All we heard in May were the usual protestations that a referendum on independence is somehow inevitable because Boris Johnson will have to accept the democratic mandate – when he obviously will not. Nicola Sturgeon was reduced to saying that demography will deliver independence because elderly Unionists are literally dying out. But independence isn’t going to happen by itself. It is a revolutionary project for a decidedly unrevolutionary time.

Enthusiasm is surely waning for one-off independence referendums that entrench divisions. The chaos of Brexit has left a residue of bitterness and confusion. No-one wants to go through all that again. Yet Scotland remains split down the middle on independence, just like the UK over EU membership. A narrow victory for independence would inevitably lead to demands for a further referendum on whatever deal

is negotiated with the Rest of the UK –just like the “People’s Vote” advocated by Nicola Sturgeon on the Brexit Withdrawal Agreement.

Anyway, the idea of a Third Way on independence has a distinguished history. Alex Salmond initially called for a devo max option in the 2014 referendum, only for David Cameron to reject it in favour of the binary. The SNP’s electoral success since the 1990s was built not on its demand for independence, but on its promotion of home rule within the UK. It is strange to hear modern nationalists resorting to the language of independence-nothing-less fundamentalists from 30 years ago.

When Salmond backed Donald Dewar’s Scotland Bill in 1998, he brought the SNP in from the cold. The Scottish Parliament gave it the platform it needed to present itself as Scotland’s national party, which is exactly what it has become. The SNP now dominates Scottish politics at every level. The latest opinion poll from Electoral Calculus suggests the SNP could win all Scotland’s 59 Westminster seats at the next General Election, which could be only two years away. Why risk all that?

Nicola Sturgeon has rejected any unofficial referendum – wisely since it would be boycotted by unionists and ignored by Westminster. Which leaves the SNP in power but powerless to move the dial on independence. Home Rule 2.0 is an obvious way to maintain progress towards independence when the legal road is blocked.

Yet, the hyper-active Glasgow councillor Mhairi Hunter says there’s no case to put devo max on the ballot paper because “no-one knows what it is”. Yes, they do. It means home rule within the overall wrapper of the United Kingdom – or “independence in the UK”, as Donald Dewar once called it – a parliament sovereign on domestic policy with tax-raising powers.

Neo-fundamentalists should remember that the SNP prospectus for 2014 called not for separatism, but for a “new United Kingdom under the Crown”. A borderless UK internal market and a common currency with England. It was essentially federalism within the EU.

Brexit has since reduced Holyrood to something more like a big unit of local government – Strathclyde Union redux. The Sewel Convention, which supposedly ensured that Westminster could not legislate on devolved matters without Holyrood’s consent, has been dumped. That needs to be reversed and Holyrood entrenched as a constitutional entity with its own sovereignty.

Similarly, the SNP’s campaign for fiscal autonomy needs reignited. The Scottish Government has the power to raise some taxes but not others – National Insurance being the most topical example. Nor does it have adequate borrowing powers. The Scottish tax base is shrinking and the Parliament needs to acquire the powers necessary to ensure that Scottish growth does not continue to lag England’s.

Tax revenues also need taxpayers and Scotland’s population is dwindling again, post-Brexit, and getting older faster. Scotland needs those powers over immigration, promised before Brexit, to be honoured. More people of working age are going to be needed to pay the taxes to finance social programmes like social care and the child payment.

The refusal to explore options short of full independence also closes off debate about Europe. Could Scotland emulate Northern Ireland by adopting regulatory alignment with the European Single Market while remaining part of the UK? That’s something even Labour could endorse. The Scottish Tories, too, would love an opportunity to distance themselves from the Johnson administration without backing independence.

Devo max would open the possibility of an SNP-Labour coalition after the next General Election. Keir Starmer has repeatedly said he could not talk to the SNP about independence, but he would talk about a new democratic settlement for the UK. Having finally capitulated to Brexit, Labour needs a constitutional mission and home rule could help provide it.

The failure of the SNP leadership to refashion the independence case to take account of Brexit has been a major lapse in its contract with the Scottish electorate. The currency question remains unaddressed along with the inevitability of a hard border after Scottish independence. The truth is the SNP has been flummoxed by Brexit and has resorted to obfuscation and denial.

There are many routes to independence. By maximising autonomy within a new United Kingdom, the SNP could even achieve functional independence without the chaos of a referendum. It was Nicola Sturgeon who drafted the 2013 White Paper on Independence, which was really a project for a federal UK. The SNP needs to go back if it is to go forward.