What can is a left-led Labour party, combined with the progressive nationalist parties and the Greens, which will institute real change.
“Progressive nationalist party” has echoes that I really don’t like. For here progressive means edging towards socialism. And nationalist socialist parties really didn’t have a good 20th century track record.
Britain has had one such quite recently, the BNP, and people like Mason tended not to like that very much. What is it about Celtic progressive nationalism that is therefore to like?