Australia needs to increase its military self-reliance so that it can approach China from “a position of strength” and prepare for the possibility that the rising power could go to war with the United States, new Liberal senator Jim Molan has said.

The retired army major-general used his maiden speech to the Senate on Wednesday to stake out his position as a defence hawk, calling for long-term investment in military readiness and linked his call specifically to China’s challenge to a US that is in “relative decline” in defence terms.

And he took a swipe against other US allies in Europe and Asia - apparently singling out Japan and South Korea - for under-investing in their militaries.

Senator Molan, who served as chief of operations in the coalition headquarters in Iraq in 2004, made headlines last week when Greens senator Adam Bandt suggested he might have committed war crimes but backed down, acknowledged he was wrong and apologised after Senator Molan threatened legal action.