DAVID Cameron's rationale for not debating with Alex Salmond - some would say his cover story - is that the decision on Scottish independence is for Scots alone, and he should not intrude.
It is an argument which is becoming more threadbare and implausible each day. It is the policy of the government Cameron leads that Scotland ought to stay in the Union. There is nothing wrong or secretive in that.
Governments have policies and pursue them, and Cameron has always said where he stood.
He famously declared, after all, that he would "campaign to keep our United Kingdom together with every single fibre that I have."
Likewise, it is the policy of the government Salmond leads that Scotland would be better off leaving the Union. Again, a perfectly legitimate policy to pursue, and hardly a surprise to the electorate.
But what is objectionable, and leaves Cameron open to charges of hypocrisy, is his scuttling away from the spotlight under the guise of principle while by their actions his ministers demonstrate no such principle exists. Cameron cannot have it both ways.
If it is right for him to keep his distance and decline Salmond's invitations to a TV debate, then it cannot also be right for his cabinet to troop round Scotland crowing about their latest paper on the hazards of independence. We see nothing wrong in Coalition ministers throwing themselves into the debate, given the UK government's openly stated policy. But there should be consistency. If the cabinet do it, Cameron should too.
Instead of holing up in Downing Street like a long-distance general, the PM should go over the top like his troops and fight.
Cameron's argument was never strong. It always smacked of a fear of being beaten by Salmond, who is itching to make the referendum a beauty contest between himself and a "Tory toff". But if it was weak on a domestic level, the PM's case is all but indefensible when set against his government's international action.
This paper has revealed talks between members of Cameron's office and the Spanish and Russian governments on Scottish independence. But as we report today, contacts between Foreign and Commonwealth Office staff and other governments on the subject appear to go far wider, soliciting adverse comment which is then fed back through the FCO's Devolution Unit.
It seems Cameron's "debate for Scots" has, through the action of his own government, been expanded into a debate for all. All except, it seems, our humbug of a PM. Cameron needs to acknowledge his role and debate with Salmond on TV.
We have had enough of the double standards.