Julian Assange's soaring rhetoric from the balcony of the embassy of Ecuador today was, by now, a rather familiar performance. The WikiLeaks founder described his gratitude to his South American hosts for taking a "stand for justice" in their offer of asylum. He told darkly of British police descending on the building last week, put off breaking the Vienna Conventions on diplomatic relations only, he said, by his supporters' vigil outside. He spoke in stirring terms of freedom of speech and the US "witch-hunt" against whistle-blowers and journalists of which he is a victim.

For all the bombast, however, the issue here is not WikiLeaks' diplomatic cables, or the US response to them, or the "dangerous and oppressive world" against which Mr Assange purports to be striving so hard. And what he signally failed to mention today was that he is all but incarcerated in the Ecuadorean embassy not because he is a fighter for freedom but because he is wanted in Sweden over wholly unrelated allegations of sexual assault.

There is no denying that the British Government sorely overplayed its hand in threatening to use laws permitting entry into a foreign embassy in order to take Mr Assange by force. Indeed, such gauche tactics have only provided him with further evidence of the persecution he believes he is suffering. But the fact remains that the commitment to pursue Mr Assange rests on the substantive criminal claims against him and the obligations of the diplomatic relationship between Britain and Sweden. Not only has the US made no move towards extraditing Mr Assange over WikiLeaks; that his fears did not extend to his prolonged stay in Britain – which is notoriously keen to oblige US extradition requests – only adds to suspicions of his motives.

Mr Assange's words may have played well with the band of hardcore supporters gathered outside the embassy in Knightsbridge today. But the spectacle of a man supposedly so committed to honesty and absolute openness going to such lengths to avoid accounting for himself is losing him much support elsewhere.