I was called a traitor by a Conservative MEP in a committee meeting of the European Parliament to which I was giving eyewitness evidence on the UK’s complicity in torture and extraordinary rendition. Doubtless that is recorded in the minutes of the meeting, which means I am marked down on a forest of European Parliament paper as a traitor in each of the European Union’s 24 official languages.

Nobody turned a hair, least of all me. There were some giggles as the Tory MEP immediately walked out of the meeting, which was viewed as childish. But nobody thought of it as way outside the normal levels of political discourse. Indeed it was quite mild by European parliamentary standards. It is, of course, perfectly true that I used to represent the United Kingdom and now it is my dearest wish to destroy it as an institution. It is therefore arguable that I am technically a traitor. I am not scared of names.

My Scottish readers will have realised that this disquisition on treachery is a reference to the Labour Party’s published dossier of evil cybernats. The majority of those cited qualified as evil because of use of the word traitor. I am devastated I did not get included. I am unsure that my ego will ever recover.

It seems to me that, in an argument which revolves around what constitutes a nation, the idea of treachery to the nation is one that logically is bound to intrude, on all sides. Indeed it can be shown to intrude into the entire discourse around unionism and nationalism over centuries. I have used the term myself.

It seems to me context is important. There is a legitimate discourse on whether treachery to either the United Kingdom or to Scotland is involved in the independence conundrum. To make plain that some consider a position or act as traitorous has a place in robust political debate. I deplore the idea that politics must be reduced to genteel commonplaces over tiny areas of disagreement. Passion is important. But to imply violent retribution is different, and comes under bullying and threat.

“Traitor” should not be shunned like a racist epithet. It carries a meaning which is important.