Andrew Hastie knew taking on Pauline Hanson would cost him. Liberals are divided over the price of following suit

While supporters and rivals of Hastie back his stance on One Nation, some are asking why the party isn’t doing more

Andrew Hastie knew his attacks on Pauline Hanson this week would come at a cost.

He was already under siege. One Nation had been taking potshots at him for months, and a section of the Western Australian media was giving them an outlet to do so.

The former SAS captain’s intent was clear from mid-June, when he told his colleagues he’d “rather get taken out in a box than bend the knee to One Nation”.

Then came an accusation contained in a One Nation cartoon – shared by Hanson herself – that he betrayed his country by giving evidence against Victoria Cross-winner Ben Roberts-Smith in a failed defamation trial .

When Hastie went hard at Hanson over the “traitor” claims, the Western Australian MP did so knowing sections of his largely conservative support base could abandon him – and that some of his own colleagues wouldn’t be prepared to pay that price.

“Andrew knows there are some colleagues that could not support him because they don’t want to be on the wrong side of what they see as a popular cause: Ben Roberts-Smith,” says one senior Liberal, who is close to Hastie but requested anonymity to speak freely.

But former Liberal prime minister Malcolm Turnbull tells Guardian Australia that Hastie “should be entitled to absolute 100% solidarity from his team”.

Hastie’s supporters acknowledge his personal pushback against smears from One Nation could take some paint off his leadership ambitions – not from within the party room, but within a membership base that doesn’t like personal attacks on Hanson and believe Roberts-Smith has been treated unfairly.

Multiple Liberal sources say this strategic assessment was evident in statements from his party leader, Angus Taylor, who called on Hanson to remove a One Nation cartoon attacking Hastie but declined to personally attack her.

The federal party’s president – former prime minister Tony Abbott, who has expressed sympathy and support for Roberts-Smith – said it would be “right” for One Nation to remove the video, but nothing more.

It was stark contrast to an emotional defence of Hastie from crossbench senator Jacqui Lambie , herself an army veteran, who accused Hanson of being an “angry little woman” and a “bloody coward” for not apologising or taking down the video.

While the vast majority of Liberal MPs have rallied behind Hastie, party insiders concede this week has highlighted a small but significant divide about the treatment of Roberts-Smith.

“There are different views within the party,” says another senior Liberal source. “On this issue, there is no consensus.”