So Hizb-ut-Tahrir

is telling followers "not to assimilate", not to cooperate with ASIO, and not to support the democratic values in the citizenship oath? They are claiming that Muslims are being "forced" to assimilate?
Yes, it's also an organisation which also supports Sharia law. Yes, it has been banned in some countries. Yes, it is radical.
Recently children were removed from a school assembly because the national anthem was about to be sung. They were removed because the children were not supposed to sing during a period of mourning for a Muslim leader. Now Hizb-ut-Tahrir is saying that being required to sing the national anthem is "forced assimilation".
There has been nothing more than the mildest of rebukes from other Muslim leaders. "They're just looking for publicity."
They got publicity. They had an extended segment on the SBS news service. Listening to well dressed, well groomed, well spoken young men speak was alarming. I have no doubt at all that they would have great influence over impressionable young people and the less well educated. Their influence may even go further than that. 
Their intention is to isolate people from society. The greater the degree of isolation then the greater control they will have over others. This is the way cults operate. It should be ringing alarm bells. Surely more moderate Muslims should be condemning this? If not, why not?
With respect to the school assembly perhaps it would have been more appropriate to simply say, "Those children not able to sing at present just stand quietly." This would both have respected their beliefs (or the beliefs of their elders) and asked them to respect those of others.
Segregating them was not the answer. It marks them out. By doing that it tells others "they're different" and "it's okay for them to isolate themselves and not be part of our society". It gives everyone the wrong message.  
So why did the media give this group so much attention? Why didn't others condemn their extremism?