A CONSTITUTION expert has warned that the greatest threat to the integrity of the United Kingdom is Unionism.

Professor Michael Keating, the chair of Scottish politics at the University of Aberdeen, told BBC Radio Scotland's The Sunday Show that the idea of Unionism is being made into one overarching idea of British Unionism, which never existed before devolution.

He noted that ideas of Unionism in Scotland and Northern Ireland were different to each other and before devolution these were given a great deal of recognition.

He said: "From 1999 the Unionist parties conceded devolution, but on the other hand they seem to have lost that sense of the Union being different things. Now that the Union is under pressure, they are trying to reinvent Unionism as something it never really was, namely a single thing right across all the nations of the United Kingdom and they just don’t fit together.  

"These Unions are very different things because these Unions are very different in nature so it’s becoming rather forced. Unionism then - rather than being an umbrella within which these various national identities could co-exist and co-operate - has become a bit of a national identity itself with all this stuff about the Britishness debate and British values."

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This difference in Unionism approaches can be seen in the UK Government having to be neutral in regards to Northern Ireland but taking an active role in promoting the Union in Scotland.

Keating said the idea of teaching "British values" to children in school, which the UK Government identifies as "democracy, the rule of law, individual liberty, and mutual respect and tolerance for those of different faiths and beliefs" are not mutually exclusive to Brits, with the SNP and other independence parties subscribing to the same beliefs.

He said: "Everybody believes in these values, there is no reason to attach that particularly to be British as opposed to being Scottish or Irish or Welsh or English for that matter."

A "more encompassing Unionism" would accept that there are people in Scotland who want to be independent, according to Keating who says they should be accommodated in the constitution, as they are in Northern Ireland.

He continued: "The Northern Ireland Agreement of course explicitly allowed for this, it said there are nationalists and Unionists, they have different long-term ambitions and that's fine, that's not a problem, we've just got to live with this rather than saying you must abandon your long-term aspirations because there's only one way to be a Unionist.

"Unionism never did that in the past. It's doing that now because it feels under threat, for good reasons with the rise in support for Scottish independence and Irish unification. It is becoming very defensive rather than being more relaxed in the way it was in the past, realising there are many different ways to belong in the Union.

"I like to compare it with the European Union which doesn't mean that you can't be French or German or Dutch, there are different meanings for the EU, we don't have to share the same understanding of what it's all about because we would never agree."

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He then went onto say that the idea of federalism in the UK is not likely to work as England would have to be included in a federal UK and the people there are "just not interested in federalism". 

He said a "federal understanding" might work, whereby Westminster has no power to legislate in devolved areas, as they currently do.

However, while Keating said the Unionists have lost the arguments, that does not mean that nationalists have won as he cited the complications Scottish independence faces from Brexit creating a hard border and around currency.

Keating thinks that a conversation needs to be had around "rethinking Westminster sovereignty" where the central UK Government respects the decisions of devolved governments and not intervene in devolved matters.

He said: "There also needs to be a rethink of intergovernmental relations. Every few years the UK Government wakes up to the reality of devolution. It's not that the UK wants to do down Scotland most of the time, it just forgets that Scotland and Wales are there."

Rethinking this constitutional arrangement, Keating says, would create "greater clarity" around which government has responsibility for different policies.