THE polarisation of the constitutional debate provided the Tories with an opportunity. They could expect to garner the lion’s share of pro-Union support. This required an uncomplicated message repeated ad nauseamthat suited Ruth Davidson’s communication skills.

The SNP was the enemy and the other parties could not be trusted. The Tories were the true guardians of the Union. It was difficult to go far wrong with this strategy. But it had its limitations. It allowed the Tories to become Scotland’s second party. A different strategy was needed if they were to become Scotland’s governing party.

It is difficult to believe that the Tories themselves expected to become Scotland’s governing party under recent leaders. This required convincing voters that they could govern competently and in the interests of a broader spectrum of the population. And that was difficult if the only message getting through was that they supported the Union. Being an effective adversarial opposition leader is much easier than becoming a potential First Minister. The Tories hit their limits under this oppositional strategy well before Ruth Davidson stood down as leader. Her ratings as opposition leader did not translate into support for her as First Minister but she kept independence at the fore of public debate as much as any politician. Little changed under her immediate successor.

But a discernible shift is now taking place. The Tories are trying to broaden their appeal and beginning to develop policies. And they are finding that developing a credible governing strategy is challenging. Their economic document ‘Power up Scotland’ is long on assertion, reasonable in diagnosing problems and challenges (not difficult as these have been outlined countless times) but short on prescriptive detail. Ignoring environmental considerations would make it easier to govern but difficult to create a sustainable future or win necessary support. There is some confusion in criticising the existing "profusion of strategies, advisory groups and discussion forums" while proposing new ones. Governing involves difficult choices, trade-offs and priorities.

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Tory education proposals are classic populist measures, designed more with an election in mind than serious public policy development. Promises of ‘000s more teachers/police/nurses are a sure sign that public policy is not the primary concern. It is fair to criticise the SNP for centralisation but absurd to then propose a centralised prescription and dishonest to promise more spending without mentioning what would be cut, or perhaps we are seeing a Tory Damascene conversion to increased taxes.

It is all very challenging and as the election draws closer, the Tories will likely retreat to the comfort of guardians of the Union in an effort to remain the main opposition party. Once they enter the terrain of presenting themselves as an alternative government, many former Labour and LibDem voters attracted to the Tories’ staunch Unionism will be tempted back to their former parties. An agenda that focuses on non-constitutional politics will likely work to their advantage. This may be Labour’s chance to replace the Tories as the main challenger to the SNP.

Governing and campaigning are very different endeavours as Boris Johnson (‘He-Who-Must-Not-Be-Named’ in any Scottish Tory propaganda this side of the Holyrood elections) is finding out the hard way. This is a lesson Douglas Ross is unlikely to be forced to learn. As the election draws nearer, he may follow his predecessors and opt to bang the union drum drowning out all else.

James Mitchell is Professor of Public Policy at the University of Edinburgh