Pauline Hanson and coalition members have been accused of fuelling Islamic extremism with comments that make young people feel ostracised.
Greens senator Nick McKim says comments by high-profile anti-Islamic figures like Senator Hanson is making it more difficult for ASIO to keep Australia safe.
"Comments that have been made from coalition members in the past few years, along with comments from Senator Hanson, have contributed to that feeling of being ostracised that in fact opens up more young people than would otherwise have been the case to being radicalised," he told parliament.
"They are playing into the hands of the very people they purport to oppose."
The Senate is debating controversial counter-terrorism legislation on Tuesday, supported by Labor, that would allow control orders to be imposed on minors from the age of 14.
Senator Hanson, who has called for a ban on Muslim immigration, hit back saying the majority of Australians were afraid of catching trains or going to shopping centres because of the threat of terrorism.
It was a shame young people were committing terrorist offences, but also reality, and people needed to be responsible for their actions regardless of whether they were children, she said.
"What do we say to the family of Curtis Cheng?" she said of the police accountant who was murdered by 15-year-old schoolboy shooter Farhad Jabar in 2015.
"People have come here not to assimilate, not to integrate... some carry with them a hatred towards us.
"If these people are not happy in our country then please go back where you came from."
Senator McKim says the government must make the case for the strong new powers, warning there's a danger control orders could become the "new normal".
Mr Cheng's murder was not in itself an argument to lower the age at which control orders would apply, he said.
"You should not and never should make laws based on the circumstances of an individual case."
Attorney-General George Brandis told Senator McKim if Mr Cheng's murder didn't demonstrate the fact minors were susceptible to radicalisation "I don't know where you learn your logic from".
"It is my job both to protect civil liberties and to protect national security and everyday of my life I grapple with the task of ensuring we get the balance right."
"It is not at all uncommon, in fact, sadly, it is very common to see at-risk people below the age of 16."
