The First Past the Post (FPTP) electoral system, admired and defended by the Conservative and Labour parties alike may yet be what does for the Union. Labour was so protective of it that in drawing up its plan for a Scottish Parliament, it insisted that 73 of the 129 members should come from FPTP constituencies, only 56 by a form of proportional representation (PR), with MSPs elected from Party lists. Labour made this concession to secure the support of the Liberal Democrats and the SNP for its proposed form of devolution. Given Labour’s dominance of Scottish politics – thanks to FPTP – in the 1980s and 90s, no other scheme would have been acceptable.

It was assumed that this would make majority one-party government impossible. Instead there would be either a coalition or a minority government depending on ad hoc support from other parties to get government business done. This was a reasonable assumption, for there were parts of the country where Labour never won seats and indeed there were constituencies where it often came third or even fourth.

The growing popularity of the SNP upset calculations. Unlike Labour, the SNP’s appeal was national, not regional.