Alex Salmond has always had a talent for soundbites, but the First Minister could come to deeply regret his comments on the Russian leader Vladimir Putin.

It is a rare example of a miscalculation by an otherwise skilled politician.

Interviewed for GQ magazine, Mr Salmond said he could see why Mr Putin has widespread support in Russia. "He's restored a substantial part of Russian pride and that must be a good thing," said the First Minister. He also said he thought Mr Putin was "more effective than the press he gets".

The First Minister did make it clear in the interview that he disapproved of a range of Russian actions, but his comments are perturbing nonetheless. They are unlikely to help his referendum campaign, or his attempts to influence those who are still trying to work out which way to vote.

The main problem is that the comments do not sit well with the SNP's explicit efforts to promote a civic nationalism based on shared values rather than an ethnic nationalism based on the accident of where you are born. The SNP has pursued this policy partly because it recognises that the worst elements of ethnic nationalism are repugnant to many voters.

The party has had some success with this policy in recent years - and has used it to specifically appeal to Labour voters. However, many voters, particularly switherers, remain worried about the less attractive nationalist emotions and their consequences. Mr Salmond's comments on Mr Putin, a classic ethnic nationalist, could stoke these worries.

The comments must also call into question Mr Salmond's judgment on this issue. His advisers point out the comments were made before the annexation of Crimea - and that an official invitation to the Russian Consul General was withdrawn after it - but the comments were certainly not made before the Russian support for Bashar al Assad's crackdown in Syria, or the suppression of the media in Russia or the targeting of minorities, including gay people. Mr Salmond says Mr Putin has restored Russian pride and that "must be a good thing", but national pride is not a good thing when it is achieved at the expense of democracy or through corruption and violence.

There is also an unfortunate parallel to be drawn with Nigel Farage, the leader of Ukip, who also expressed admiration for Mr Putin a few weeks ago and was pilloried by politicians of all colours for doing so. As the former Defence Secretary Sir Malcolm Rifkind pointed out, the Ukip leader was caught praising an autocrat who has made Russia the least free country in Europe; he also suggested Mr Farage's comments would make many British people think twice about voting Ukip.

The danger for the Yes campaign is that Mr Salmond's comments could have a similar effect on those who are still undecided, particularly women who are not comfortable with macho nationalism and could be even less comfortable with Mr Salmond's apparent endorsement of elements of it. The problem for Mr Salmond and his colleagues has always been that they face the challenge of promoting the "right" kind of nationalism rather than the "wrong" kind. The First Minister's comments have made that challenge considerably harder.