General Election 2015: When push comes to shove, the SNP will be forced to back Miliband

If the polls are correct (and do not change significantly over the next few weeks), it looks likely that on 8 May we will wake up with a party that doesn’t want to be part of the United Kingdom holding the balance of power in the UK Parliament.

But just how much of a whip hand would the Scottish National Party (SNP) exert in Westminster? Could it, as the Conservatives claim, force Labour to scrap Trident, allow Scottish workers to retire earlier or even force another independence vote?

The answers to those questions are: very little and no.

The reason is that while the SNP might have notional power in the seats it wins, it is completely boxed in by its own political situation. Take this quote from the SNP leader, Nicola Sturgeon, in the Scottish leaders’ debate: “The SNP will never ever be part of supporting the Tories into government.” She added: “I don’t think we want a formal coalition either – but what I have said is we will work with Labour to keep the Tories out.

“So if there are more Labour and SNP MPs than there are Tory MPs then we would [have] a vote of confidence to stop a Tory government even getting off the ground.”

The SNP would lose all credibility (and votes) among its own supporters should it ever knowingly allow a Conservative government to win power. But this position also removes any potential for the SNP to demand policy concessions from Labour as a price for its support.

All Ed Miliband needs to do is call the SNP’s bluff: sure, he will say, oppose us if you want, but that will just trigger an election that could let the Tories in. Is that really what you (or your voters) want? This point is particularly important because next year the SNP and Labour will both be battling it out in elections for the Scottish Parliament – that are arguably much more important for Sturgeon than the general election.

If the SNP is held to be responsible for destruction of a progressive alliance in Westminster, it could lose its new supporters north of the border as well. That is not to say the SNP might not oppose a Labour government on issues such as Trident – but then, as the Tories have made clear, they support replacing Britain’s independent nuclear deterrent so will have to support Labour to get the measure through the Commons.

So Labour can ignore the SNP, safe in the knowledge that when push comes to shove on a vote of confidence in Ed Miliband’s government it will be forced to support him.

Miliband just has to do well enough in the election first.

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