A few weeks ago, I watched Nicola Sturgeon speak at a Scottish CND rally in Glasgow’s George Square. There were, at most, 200 or 250 people in the crowd. As Scotland’s deputy first minister, Sturgeon must have had a dozen more important things to be doing. She certainly wasn’t winning any new converts to independence – most of the audience arrived sporting Yes campaign badges and placards. But she still delivered a pretty good speech – one she had obviously spent time preparing.
It is difficult to overstate the strength of the SNP’s opposition to nuclear weapons. The current generation of SNP leaders grew up marching against Polaris in the 1970s and its replacement, Trident, in the 1980s. For nationalists, the presence of nuclear submarines on the Clyde symbolises both Scotland’s lack of sovereignty and Westminster’s disregard for Scottish interests. Unilateralism is in the party’s blood.
For this reason, I’m sceptical of claims the Scottish government plans to use Trident as "leverage" during the negotiations that would follow a Yes vote in September – although I can understand why it might be tempted to.
Trident would be a powerful bargaining chip. Westminster politicians cling to the nuclear deterrent because they fear Britain’s international status would be significantly downgraded without it. So it’s not hard to imagine the UK offering Scotland favourable terms of divorce (currency union, an equitable division of military assets etc.) in exchange for Trident remaining in Scottish waters until an alternative base could be built south of the border.
The prospect of such a deal has already been raised by one high-ranking UK cabinet minister and there are even some in the Yes camp (including, curiously, veteran leftist Jim Sillars) who think the Faslane and Coulport bases should be leased back to Britain after independence.
There is, however, little sign that the SNP leadership is open to compromise. When I talked to people at the top of the party in 2012 and 2013, they were vague about how long it would take for Trident to leave the Clyde. But their position seems to have firmed up since then. At the launch of the White Paper in November, Nicola Sturgeon was clear that she wanted Trident gone by the end of the first term of an independent parliament. More recently, in his now infamous GQ interview with Alistair Campbell, Alex Salmond warned Westminster not to "underestimate [his] determination" to get rid of Trident, while Angus Robertson, the SNP’s defence spokesman, has insisted the submarines will be out by 2020.
It’s possible this is just rhetoric; an attempt by the SNP to stake out a negotiating position in advance of a Yes vote. This approach would fit with what one senior defence analyst (and opponent of independence) told me last summer: that the UK government could probably construct a new site for Trident within ten years – as opposed to the current official estimate of 15 to 25 – if the Scottish government was prepared to "accommodate" Westminster’s demands, such as leaving the warheads operational and under UK control.
But even a modest U-turn on Trident would incur heavy political costs. To begin with, it would undermine the SNP’s internal unity. Like their leaders, many nationalist activists have spent their lives marching against nuclear weapons and view Trident’s departure from Scotland as one of the main prizes of independence. Likewise, if Scots vote Yes in four months’ time, they will do so under the expectation that Trident will go. The SNP would lose a lot of credibility if it suddenly abandoned one of the key features of its independence prospectus.
There are other complicating factors. The SNP has earmarked Faslane as the site of a future Scottish naval base and wants to impose a constitutional ban on the stationing of nuclear weapon in Scottish territory. At the same time, the party supports Scottish membership of NATO and says Scotland will adhere to the Alliance’s "don’t ask, don’t tell" policy, which would (controversially) allow nuclear submarines to travel through Scottish waters without the explicit consent of the Scottish government.
Nonetheless, Trident is a red-line issue for the nationalist grassroots, for much of the broader Yes campaign and, it seems, increasingly, for the SNP top brass. If there is a Yes vote, Westminster is going to face an almighty battle to keep Trident in Scotland beyond 2020. The UK government would be wise to start drawing up contingency plans, if it hasn’t done so already.