UNIONISTS have been concerned for some time about the way the Scottish Government seems to have been able to get away with developing aspects of its own foreign policy, despite this being one area of governing which supposedly is well and truly reserved to London.

Thus, the Scottish Government has set up a series of overseas trade missions, ostensibly to promote Scottish goods and services but, to sceptical eyes, looking more like mini embassies-in-waiting. Similarly, Holyrood passed its own Brexit legislation.

On one view this was just to ensure that norms and ideas derived from EU law could continue to play a role in Scots law even after Brexit. But on another it was the opening salvo in an underhand Scottish attempt to negotiate its own legal relations with the EU, in a manner plainly contrary to the devolution settlement.

Concerns over such matters are serious. But what really furrows brows in the Foreign and Commonwealth Office is when Scottish Ministers make statements about foreign policy which are straightforward attempts to undermine UK policy. One flashpoint is Israel.

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Israel is one of the United Kingdom’s principal allies in the Middle East. Trade between Britain and Israel is worth more than £4 billion annually and, at the same time, the two countries maintain an exceptionally close defence and security relationship, sharing intelligence, military co-operation, and logistics.

One may think that matters should be otherwise – even for its friends, Israeli policy is not exactly becoming easier to defend. It is not just the country’s treatment of the Occupied Territories: it is also what is happening right now inside Israel, as the country slips its democratic moorings and slides towards an authoritarian populism more associated with Erdogan’s Turkey or Viktor Orban’s Hungary than with the Zionist dream of a democratic Jewish state.

The Herald: 'The country slides towards an authoritarian populism more associated with Erdogan’s Turkey than with the Zionist dream of a democratic Jewish state''The country slides towards an authoritarian populism more associated with Erdogan’s Turkey than with the Zionist dream of a democratic Jewish state' (Image: PA)

But, whatever one thinks of the policies of the current Israeli government, the point is this: the United Kingdom’s diplomatic relations with Israel – or indeed with any other state – are a matter for the United Kingdom Government and not for Scottish Ministers. Unless and until Scotland becomes an independent state in its own right, foreign policy will be set by the United Kingdom Government alone.

So, strap in. Because there is going to be a big row about this. A largely unnoticed line in the Conservatives’ 2019 election manifesto pledged the party to “ban public bodies from imposing their own direct or indirect boycotts, disinvestment or sanctions campaigns against foreign countries”. The pledge was expressed generally but we all know there is only one well-established BDS ( Boycott, Divestment, Sanctions) campaign in the UK – and that is the pro-Palestinian BDS campaign against Israel.

The pledge has not yet been legislated for. But, I understand, legislation is under preparation and may now be expected sooner rather than later. When it comes, all eyes in Bute House will be on whether the legislation applies only to public authorities in England or to public bodies across the whole of the UK, binding the Scottish Government as much as it binds, say, Leicester City Council.

Now, imagine for a moment those eyes are Humza Yousaf’s. His wife, Nadia El-Nakla, has family in Gaza. In the pursuit of public policy touching on the Middle East, it is unlikely, I should have thought, that a Yousaf-led Scottish administration will view Israeli-Palestine politics from the same perspective as the Foreign Office.

Certainly the SNP’s current coalition partners, the Scottish Greens, whom Mr Yousaf would like to retain in office alongside him, take the hardest of hard lines when it comes to Israel.

Of course, Mr Yousaf may fail in his bid to lead his party. His only serious rival, Kate Forbes, would be likely to take an altogether less confrontational line. Picking fights with the UK over Israel is unlikely to be high on Ms Forbes’ agenda. But if Mr Yousaf becomes First Minister later this month, it’s odds-on we’ll hear a good deal more in Scotland about Israel, Palestine and the politics of BDS.

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Nearly a decade ago Leicester City Council passed a motion resolving to boycott any produce originating from settlements in the West Bank until such time as Israel withdrew from the Occupied Territories. The campaign group, Jewish Rights Watch, took Leicester City Council to court, arguing that its motion was unlawful, not least because (they argued) it breached the Equality Act. Jewish Rights Watch lost the case, the court ruling in the city council’s favour.

More recently, when David Cameron and Theresa May’s governments moved to restrict the ways public sector pension fund managers were able to divest from Israel, the Palestine Solidarity Campaign took the government to court, arguing that ministers had acted unlawfully, in breach of pensions law. They won, the court ruling against the UK government.

The Conservatives’ 2019 manifesto pledge is designed, in effect, to reverse the results of court cases such as these. In the government’s view, it is inconsistent with British foreign policy for local authorities to be able to boycott goods and services originating from one of the United Kingdom’s principal strategic allies.

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It is likewise contrary to foreign policy for public sector pension fund managers to be permitted to divest funds from Israel, when British trade there is such an important component of the UK’s business in the Middle East.

But it is not just local authorities in England and public service pension fund managers which the UK Government will need to have in its sights if its manifesto commitment is to be made good.

The time is coming for devolved administrations who think it part of their business to undermine the established foreign policy of the United Kingdom to be stopped. There is going to be a row about this, but it is a row the UK will inevitably win, one way or the other – regardless of who peers out from the behind the Bute House curtains come the end of the month.

Adam Tomkins is the John Millar Professor of Public Law at the University of Glasgow School of Law. He was a Conservative MSP for the Glasgow region from 2016 to 2021.