There's an article by a "Macmillan" about the failure of the UK Conservative Party in Northern Ireland. Scotland and Wales are the same: dissatisfaction with the constitutional status of the country as part of a larger country trumps "normal" Left/Right politics about the economy and society.
In the US, there's no identity politics involved in opposing the Federal government, therefore the localist States' Righters end up as supporters of limited government, on the Right. In the British Isles, things couldn't be more different: most parties other than Labour and the DUP stand to gain from the breakup of the Union: the Conservatives and SNP are effectively the English and Scottish mainstream non-Labour parties. Or to put it another way, the SNP plays within Scotland that structural rôle which would in England be played by the Conservatives.
It's not clear whether ideological centre-Right or centre-Left parties are viable in the presence of a "national question". The UK as a whole has its "national question" in the form of Europe: if the EU is seen is bigger and richer, then we should expect British nationalism against the EU to be on the Left, otherwise, as at present, on the Right.
This all gets me wondering, what would Dev have done about the EU?