Understandably, members of the LGBT community feel no particular love for the ACL. However, a campaign to embarrass the Hyatt for its alleged "support" of a group opposed to same-sex marriage will strike impartial observers as uncomfortably close to the kind of vilification of which minority activist groups so frequently complain. The theme of the two-day ACL conference is "Speak Up", which is taken from Proverbs 31:8, the more modern translations of which read "Speak up for those who cannot speak for themselves; ensure justice for those being crushed".

Across town, a public debate on terrorism to have been held at the Australian National University was cancelled after a number of academics invited to take part in discussions sent their regrets. The debate, an initiative of the campus newspaper Woroni, was to have included Wassim Doureihi, a spokesman for Hizb ut-Tahrir Australia. The group, whose aims include the establishment of a global caliphate under strict sharia law, has been proscribed as a terrorist group in many countries but not Australia. Nonetheless, many people, Prime Minister Tony Abbott included, regard Hizb ut-Tahrir as a purveyor of dangerously seditious ideas and a defender of abhorrent practices, including honour killings. Indeed, another Hizb ut-Tahrir spokesman, Uthman Badar, accepted an invitation to give a public lecture at Sydney's Festival of Dangerous Ideas in July entitled "Honour killings are morally justified". But festival organisers cancelled it after public anger over the topic to be canvassed. Mr Doureihi is also no stranger to controversy, having recently evaded questions put to him on national television about whether his group condemned the murderous campaign being waged by Islamic State in Syria and Iraq.

Mr Doureihi's scheduled appearance was undoubtedly the catalyst for the ANU debate's cancellation. There is a suggestion that some of the other speakers were initially unaware that Mr Doureihi had been invited – and that when they were apprised were uneasy about the potential for his appearance to transform what was intended to be a formal discussion about terrorism in Syria/Iraq into a Hizb ut-Tahrir propaganda event. Given Mr Doureihi's blustery style and propensity for talking over the top of others, such fears were probably well founded. Nonetheless, those who believe in freedom of speech and spirited public discourse (of which Woroni, and by extension, the university should be exemplars) would have been somewhat disappointed by the academics' decision. The individuals who took to social media to try to try to tar the Canberra Hyatt hotel as somehow being an accessory to the "intolerance" of ACL showed a similar lack of awareness about the need to confront erroneous, ill-informed or bigoted thinking head-on rather than seeking to avoid it or, worse, shut it down.

The beliefs that Hizb ut-Tahrir Australia hold dear - and to a lesser extent those held by the ACL - are an affront to many people. To howl them down or delegitimise, however, is to risk adding to their sense of tenacity and purpose, perhaps to the point that they go underground and becoming a even greater nuisance or threat. Sunlight being the best disinfectant, ideas good and bad need to be debated in public. And if some are considered beyond the pale, sedition and defamation laws provide ample protections for injured parties.

The belief that Australians can and do exercise freedom of speech is a myth. The constraints on it, legal and otherwise, are onerous. And those checks will remain in place, despite promises by the Abbott government to dismantle some of the egregious ones. That some people should seek to further restrict public discourse (using the concepts of "tolerance" and "dignity" as cover) needs to be recognised for what it is, humbuggery, and resisted.