They could let the Scots run the UK. They seem to know what they're doing.
No? Is there no-one the country might rally behind? Anyone? Leaders of vision and courage are now needed - are there any who might emerge?
The problems of the UK are the problems of modern democracy writ large. The US founders, classical republicans all, expected that the country would elect wise far-seeing statesmen to lead the USA. Instead the country was dominated by mechanics and shopkeepers, and the demagoguery was beyond belief. It elected the slaving, genocidal Andrew Jackson, who left the USA in a shambles for generations.
They didn't know. They couldn't know. But we do know. What now?