By Christopher McLean
Recent polls have shown a decline in support for independence, a trend which many commentators have attributed to the impact of the Queen's Diamond Jubilee and Team GB's performance at the London Olympics. It's been argued that the consequent promotion of 'Britishness' has strengthened support for the Union.
Likewise, some have argued that the SNP's decision to hold the referendum in 2014 is based on an assumption that the combination of the Commonwealth Games being held in Glasgow and the 700th anniversary of the Battle of Bannockburn will generate an increased sense of 'Scottishness', boosting the chances of a 'yes' vote.
This begs the question: what impact will public feelings of national identity have on the outcome of the referendum?
Evidence does suggest a link between national identity and attitudes towards independence. Our most recent poll, conducted in June, found two-thirds of those who described themselves as Scottish not British support independence, while over three-quarters of those who described themselves as equally British and Scottish oppose it. Indeed, trend data from the past 20 years shows that fluctuations in the proportion of the population who consider themselves Scottish and not British reflect changes in support for independence.
A closer look at the data provides some hope to both sides of the campaign.
For the nationalists, the relatively high proportion of Scots describing themselves as Scottish not British between 1999 and 2001 closely followed devolution and the opening of the Scottish parliament. This would suggest that the campaign for devolution went some way to instilling a greater sense of 'Scottishness' among the population. Could a similar campaign ahead of the referendum do likewise?
The unionist camp can take heart from the fact that, minor fluctuations aside, the trend over the last ten years suggests that Scots are becoming less inclined to consider themselves Scottish rather than British. This may be the result of Scots becoming more comfortable with the constitutional settlement following devolution. Our polling consistently shows a stronger preference among Scots for further devolution rather than outright independence, which may work in the unionists' favour if they can articulate the advantages of devolved government within the union.
However, it would be dangerous for either side to concentrate too strongly on accentuating either 'Scottishness' or 'Britishness' in the forthcoming campaign.
The link between national identity and attitudes towards independence is particularly clear cut when explaining partisan positions. Those who consider themselves as exclusively Scottish are far more likely to vote 'yes', while those who consider themselves equally British and Scottish are far more likely to vote 'no'. These positions will be difficult to change and are likely to become even more entrenched as the referendum approaches.
The group which will be of greatest importance to both camps, is made up of those who describe themselves as more Scottish than British. Attitudes towards independence are finely balanced among this group: 45% oppose independence, 38% support it and 12% are undecided. The proportion of Scots in this group (around a third of the adult population) has been relatively stable, particularly in the last ten years, which suggests they are less likely to be swayed either way by nationalistic sentiments. They are also exactly the group that both sides need to win over in order to secure victory.
Christopher McLean is a researcher with Ipsos MORI Scotland and a regular commentator on Scottish politics and the independence debate.
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