As controversy over Australia’s new hate laws continues, last weekend’s so-called March for Australia rallies were the latest in a string of events that have raised the temperature of public debate.

It’s hard to generalise about the motivations of those involved. Politicians representing Pauline Hanson’s One Nation party attended. So did members of the wider community who oppose immigration policies and a smaller number of more extreme agitators.

Some people crossed a line into criminal behaviour. One man was charged with inciting racial hatred against Jewish people. Police are investigating another man for throwing a bomb into the crowd at an Invasion Day rally in Perth.

The neo-Nazi group National Socialist Network formally disbanded to avoid the new hate offences passed earlier this month. But links have been uncovered between its former members and rally organisers. It remains to be seen how the authorities will approach far-right groups who continue to operate while skirting the law’s boundaries.

The strong anti-immigration sentiment expressed at these rallies raises complex questions about freedom of speech, rights to political protest and growing threats of extremism.

A fundamental source of these challenges is the difficulty in saying – especially in a democracy that values freedom of speech – when someone crosses the line from legitimate social and political beliefs into “extremism”.

It now seems rare for a day to go by without some mention of........

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