Amid the estimated 100 protesters, 50 police, a noisy helicopter and rained-on press corps gathered in Knightsbridge on Sunday afternoon, two women were missing. They are referred to as Miss A and Miss W – that is, when they are mentioned at all in the hullabaloo over Julian Assange. Yet Miss A and Miss W are at the heart of this story, however convenient it may be for Mr Assange's supporters to elide them.

After all, it is their allegations that Mr Assange sexually assaulted them two years ago that are the reason why the WikiLeaks founder faces extradition to Sweden. It is to avoid questioning by Swedish prosecutors that Mr Assange battled extradition orders for almost 18 months with the best legal representation money can buy – before finally jumping bail two months ago. It is to avoid being confronted with accusations of rape and sexual assault that Mr Assange is now holed up in the Ecuadorean embassy – and was forced to say his piece from a diplomat's first-floor balcony, for fear of otherwise being collared by the police. Yet to listen to the speechifying from his supporters, you would never have guessed at any of this; their remarks concerned western Europe's "neocon juntas" or the political change sweeping Latin America. And when it was Mr Assange's turn to speak, he allied his struggle with Russian punk protesters Pussy Riot, with the New York Times, and indeed "the revolutionary values" upon which America was founded. This is his traditional method of argument: to conflate a number of causes – big and small, international and individual – into one, so that Mr Assange is WikiLeaks, which is freedom of speech, which holds powerful states to account; and so on, ever upwards. Yet Mr Assange is not facing a show trial over the journalism of WikiLeaks; he is dodging allegations of rape. To confuse the two does no favours to the organisation he created, which has done so much excellent work.

It is commonly accepted that such allegations take a huge toll, with those making them forced to divulge intimate details. In the case of Miss A and Miss W, it is worse. Mr Assange's legal team has referred to the case as a "honeytrap"; and their own lives have been smeared across the web by self-styled followers of WikiLeaks. Imagine enduring nearly two years of that and then watching the man you believe assaulted you addressing an adoring throng on the subject of oppression. His one point that did deserve amplifying was about Bradley Manning. Accused of giving classified material to WikiLeaks, the US private has been locked up without a trial, and subjected to treatment that Hillary Clinton's own spokesman, PJ Crowley termed "counterproductive and stupid" (before being forced to resign).

But there is much else that doesn't stack up in Mr Assange's presentation of his case. This champion of radical transparency hasn't helped Swedish prosecutors with their inquiries. There was his remark about people being jailed for exercising freedom of speech, "There is unity in the oppression. There must be absolute unity and determination in the response", and yet taking shelter in a country that, according to Reporters Without Borders, shut down six radio stations and two TV stations in just one fortnight this June.

And ultimately there is the repeated suggestion from Mr Assange's supporters that if he goes to Sweden he will face extradition to the US to be prosecuted for treason. Yet there is no serious evidence that Washington plans to start such proceedings; and if it ever did, the political and public opposition in Sweden as well as Britain and across the world would be massive. But that is precisely the point: the valuable service performed by Mr Assange at WikiLeaks is a different issue from the serious accusations facing him in Sweden. Conflating the two may provide a rhetorical rush, as it did in Knightsbridge on Sunday; but over the longer term it badly damages the reputation of WikiLeaks and does Mr Assange's case no practical good.

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