Dumped Prime Minister Tony Abbott says there are too many Muslims who support the idea of “death to the infidel”, in an opinion piece published on Wednesday.

Writing for News Corp in a piece titled “The religion of Islam must reform”, the devout Christian explains that “we [the West] can’t remain in denial about the massive problem within Islam”.

“Islam needs to delegitimise the urge to ‘behead all those who insult the Prophet’ but only Muslims can do this,” Mr Abbott wrote.

“We should be ready to proclaim the clear superiority of our culture to one that justifies killing people in the name of God.

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“In Australia that means talking to decent people who happen to be Muslim as well as to ‘official’ Muslims inclined to see ‘Islamophobia’ in any criticism.”

Mr Abbott also branded arguments blaming Western policy for Islamic extremism “self-excusing rubbish”.

“Saturday’s Daily Telegraph reported local Muslim leaders blaming Islamic State on Western foreign policy but this self-excusing rubbish ignores the fact that the death cult’s victims have mostly been Muslims who think differently,” he said.

“It’s also time Australians stopped being apologetic about the values that have made our country as free, fair and prosperous as any on Earth.”

Mr Abbott – a Rhodes scholar and one time trainee priest – argued that because Islam had not had a “Reformation” or “Enlightenment”, it had not yet modernised.

“Islam never had its own version of the Reformation and the Enlightenment or a consequent acceptance of pluralism and the separation of church and state,” Mr Abbott said.

“Fortunately there are numerous Muslim leaders who think their faith needs to modernise from the kill-or-be-killed milieu of the Prophet Mohammed.”

The former PM said showing respect for Western values and denouncing radical Islam should not be viewed as culturally insensitive.

“Where hate preaching is not illegal it should at least be thoroughly answered point-by-point with a very robust defence of human rights and responsibilities,” Mr Abbott said.

“It’s not culturally insensitive to demand loyalty to Australia and respect for Western civilisation. Cultures are not all equal.”