Home Affairs Minister Peter Dutton, whose department has overseen the revoking or refusal of visas for a range of different figures in the past, is holding firm against Labor’s push to ban Kassam.
He suggested it’s a “slippery path” not to let alternative views be debated in a civil way.
“People have a right in our country, I hope it's always the case, you can express views, you can argue against it vehemently if you like,” Mr Dutton told The Today Show.
“I worry in our country, as we are seeing in other democracies at the moment, that views are shouted down, either because they are politically incorrect or people don't agree with them.
“It's a very slippery path. I think allow people in a democracy like ours to have their say, to have a civil debate then make up your own mind.”
So who else has Australia banned in recent years? It’s not just political activists - from conspiracy theorists, Palestinian campaigners, American rappers, to anti-vaccination advocates – the list is diverse.
The conspiracy theorist: David Icke
Just hours before he was due to board a flight to Australia for a speaking tour in March 2019, the Home Affairs Department banned the 66-year-old conspiracy theorist from entering the country.
The controversial figure is known for suggesting that the world is run by alien shape-shifting reptiles including the British royal family.
He’s also an accused Holocaust denier and once was quoted saying Jewish people financed Adolf Hitler to power.
Jewish groups including The Anti-Defamation Commission who campaigned against Icke’s arrival in the country celebrated the ban.
“This was a defining moment for who we are as a nation, and we salute the government for taking a clear-eyed and moral stance in rejecting hate and incitement,” Dvir Abramovich, Chairman of the Anti-defamation Commission said.
The alt-right firebrand: Milo Yiannopoulos
After a backlash from coalition MPs and conservative media commentators, Yiannopoulos reportedly had his visa personally approved by Immigration Minister David Coleman in March 2019.
But only a week later the government made an about-face and banned the controversial figure after he published comments describing Islam as a "barbaric, alien" religion, following the Christchurch mosque massacres in which 50 people were murdered.
Mr Coleman said the comments were “appalling” and fomented hatred and division.
Yiannopoulos owes some $50,000 to Victoria Police for riots outside his 2017 Australian tours in which five officers were injured.
The 'western chauvinist': Gavin McInnes
The Canadian founder of the far-right group The Proud Boys was due to tour major Australian capital cities as part of “The Deplorables” tour in 2019 when he was denied a visa on character grounds.
A petition by Melbourne lawyer Nyadol Nyuon was taken to federal parliament calling on Mr Coleman to deny a visa to McInnes, who was described in the petition as, “A man who encourages violence, who formed a gang labelled a hate group and that serially engages in violence”.
The Proud Boys, which is dedicated to upholding “western chauvinist values”, is classified by the FBI as an “extremist group with ties to white nationalism”.
Asked about the ban, Home Affairs Department at the time would not comment individually on McInnes but said non-citizens must satisfy a character test.
"For visitors who may hold controversial views, any risk they may pose will be balanced against Australia’s well-established freedom of speech and freedom of beliefs, amongst other relevant considerations,” a spokesperson said.
The whistleblower: Chelsea Manning
Manning, who served seven years in jail for leaking classified military and diplomatic documents to WikiLeaks, was denied entry into the country in 2018 because of her criminal record.
The Australian government refused to grant Manning a visa based on a “character test” in the Migration Act, which stipulates that a person can be barred entry to the country if they have been sentenced to a prison term of one year or more.
She was scheduled to speak at the Sydney Opera House in September 2018.
Human rights groups rallied to have the ban overturned on free speech grounds.
The Palestinian activist: Bassem Tamimi
In 2017, Bassem Tamimi, a prominent activist against West Bank settlements, had his visa cancelled before he was due to travel for a speaking tour in some Australian capital cities.
Tamimi is the father of Ahed Tamimi, the teenager who served about seven months in prison for slapping an Israeli soldier.
The Immigration Department said it banned Tamimi because his presence could lead others to “react adversely”.
“The Department recently became aware of information that indicates there is a risk that members of the public will react adversely to Mr Tamimi’s presence in Australia regarding his views of the ongoing political tensions in the Middle East,” it said at the time.
The anti-vaccination campaigners: Kent Heckenlively
In 2017, the self-proclaimed "world's number one anti-vaxxer" was refused entry by then-immigration minister Peter Dutton, saying it was not in the country’s national interest to allow his arrival.
“These people who are telling parents that their kids shouldn't be vaccinated are dangerous people and we have been very clear in having a look right through this particular case and it's clear to me that it's not in our national interest that he should come here,” Mr Dutton said at the time.
But Heckenlively wasn’t the only anti-vaxxer banned that year – Briton Polly Tommey and American Suzanne Humphries were issued a three-year ban after showing a film in Australia linking the debunked theory that vaccines cause autism.
The US rappers: Skepta and Tyler, the Creator
In 2015 Tyler, the Creator claimed he was banned from entering the country after feminist group Collective Shout petitioned to have him blocked on the grounds that his work promoted violence against women.
The Californian rapper was scheduled to play in Brisbane, Melbourne and Sydney that year but he cancelled the tour.
In 2013 he was accused of directing an abusive tirade against a Collective Shout activist on stage.
But he could be back soon: the rapper is due to headline the Wildlands Festival in Brisbane in December 2019.
There, he will be joining UK rapper Skepta, who initially faced a departmental visa ban in 2018 which was later overturned.
The British rapper, whose real name is Joseph Junior Adenuga, was reportedly denied a visa in April 2018 after a delegate for Home Affairs Minister Peter Dutton knocked back his application on character grounds.
It’s believed that was related to a 2016 incident in which he punched a man at a Melbourne nightclub.
An appeal against the ban was upheld with an Administrative Appeals Tribunal of Australia official saying he accepted the rapper posed a “low risk” of re-offending, in part because the victim accepted an apology and invitation to attend a concert later that year.
The Tribunal also concluded that: “Mr Adenuga has achieved substantial career success and embarked on charitable and commercial enterprises since January 2016.”