The Australian government must immediately grant US whistleblower Chelsea Manning an entry visa so she can commence her long-planned speaking tour of the country.

Manning, who is due to speak in Sydney on Sunday, was a junior intelligence analyst in the US military when, in 2010, she provided WikiLeaks with more than 700,000 classified military and diplomatic documents.

These “Iraq war logs” and the “Afghan war Diary”, as they became known, exposed summary executions by US soldiers, video of an Apache helicopter crew revelling in the slaughter of civilians and a US spying operation on leaders of the United Nations, among other things.

Manning received a “notice of intention to consider refusal” of her visa from the government on Wednesday. The notice referred to the “character test”, which was added to the Migration Act by Peter Dutton when he became minister for immigration in December 2014.

The character test itself is onerous and objectionable, yet another means for the government to restrict entry to the country. That it is used as a potential means to deny Manning entry is testament enough to that.

More broadly, the government’s threat is yet more evidence, if any were needed, that the political right’s ongoing campaign about supposed left wing restrictions on free speech is utter hypocrisy.

The right and the far right in Australia have the largest platform for their reactionary views: a conservative federal Coalition government, an unrepresentative Senate with outspoken far right campaigners and a print media largely controlled by the reactionary Murdoch empire.

All this, however, is not enough. The government still wants to restrict the number of voices engaged in the official public debates.

The usual suspects clamouring to denounce a so-called lack of diversity in public debate have gone silent about Manning – as they have in the face of every institutional attack on freedom of expression or association directed against the left.

This is not surprising. All their campaigning about free speech is just an attack on opponents of racism, imperialism and bigotry.

We need more voices like Manning: principled, honest and committed to transparency.

She should be let in so her speaking tour can commence.