Could the Scottish Government's Continuity Bill become the unlikely spearhead for a new push towards independence? Titter ye not. Stranger things have happened.

Nicola Sturgeon’s bill aims to ensure that the Scottish Parliament hangs on to all devolved competencies returning from Brussels after Brexit – and that means 111 out of 111 powers, not just the lion’s share.

Theresa May wants a temporary freeze on devolving 25 powers, until harmonised frameworks are agreed across the UK. That means Westminster hangs on to food standards, genetically modified crops, animal welfare and food hygiene in case separate Scots standards stymy foreign trade deals or complicate trading at home.

However reasonable or insignificant that sounds, the Scottish Government won’t budge because there are some mighty issues at stake.

Nicola Sturgeon is not going to let the Westminster government walk all over devolution. Picture: Getty

First, the Scottish Parliament is not stuffed with carnaptious idiots. If there is no good case for deviating from UK-wide regulations, and if all parties are treated with respect and given time to negotiate, no self-harming Scottish regulations will appear. Why would they? For the all-controlling Westminster government, that common sense reality isn’t good enough. To eliminate the slightest scintilla of doubt, Mrs May is prepared to stamp all over the devolution settlement, show who is boss and demonstrate how weak the Scottish and Welsh Parliaments really are. Whaur’s the “most powerfully devolved Parliament in the world” noo then?

This unlovely display of force majeure proves that Westminster trusts Holyrood as much as controlling parents trust bairns with ten shillings in a sweetie shop.

That’s why Nicola Sturgeon is digging in and threatening to deploy shame and inconvenience because they are the only powers Holyrood really has. She is urging MSPs to refuse consent for the UK government’s Withdrawal Bill to throw a Scottish spanner in the works. The bill will pass anyway but without the unresolved provisions relating to Scotland, leaving a legislative gap the Continuity Bill seeks to fill by bringing relevant EU laws across to Holyrood so that MSPs and Scottish ministers can amend or repeal them – not Westminster. A similar bill was prepared before the independence referendum in 2014. Of course there is already disagreement over legality – the Presiding Officer says this mechanism isn’t within the competence of the Scottish Parliament but the Lord Advocate and the Welsh Presiding Officer think it is and several peers say the Lords will not allow the Withdrawal Bill to proceed without devolved consent.

So this week we are heading for a constitutional crisis over devolution which could easily escalate if Theresa May isn’t careful. And she isn’t.

Admittedly, fertiliser composition and food hygiene may seem unusual triggers for indyref2. But just as Al Capone was finally convicted for tax evasion, so the tone deaf Tory government could yet be hoist on its own petard, creating more united opposition in Scotland to its neurotic power grab than its woefully inept handling of Brexit. Constitutional break-ups are often sparked into life by relatively small things.

Take Norway. Its unilateral declaration of independence from Sweden in 1905 was triggered by the supremely unimportant sounding issue of consular representation. In 1814, when Norway was given its own parliament, Sweden retained control over foreign affairs and defence. This irked Norwegians whose massive shipping industry was the fourth largest by tonnage in the world, so after 90 years of recurring disputes, Norway demanded sole responsibility for consular representation at foreign ports of call. Sweden remained adamantly opposed. Norway’s parliament followed with a declaration of independence. Hostilities were averted by a referendum in August 1905 in which 368,208 Norwegian men voted to end the union, while only 184 voted against – women didn’t have the right to vote.

Now I’m not saying Scotland is Norway. For one thing there is not unanimity on the case for independence here, just as Scotland has not had Norway’s long history of truly powerful self-government since 1814. But no-one guessed an issue like consular representation could possibly spark the break-up of a 90-year-old Union of Crowns before politicians tumbled deeper and deeper into the impasse.

Some big questions arise.

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