A senator and a former senator have taken aim at Australia’s massive $368 billion submarine deal.

Former Independent Senator for South Australia, Rex Patrick, who is himself a former submariner, says the submarines are useful, but he’s not sure they justify the cost.

“The question is whether or not we should be spending north of $300 billion on a single capability. Whether that is a) affordable and b) is correct in terms of the opportunity cost — other things we could be buying for the Australian Defence Force that simply would not be bought because of this spend,” he told Neil Mitchell.

“We could have 20 conventional off-the-shelf submarines built here in Australia for about $30 billion.”

Press PLAY below to hear why Mr Patrick is concerned

Senator for NSW and Greens defence spokesperson David Shoebridge has taken aim at the mega defence spend, which he says isn’t in Australia’s strategic interest.

“I, together with millions and millions of Australians are objecting in a time of peace to see our defence budget overwhelm — and this is what $368 billion means — our spending on Medicare, our spending on housing, our spending on education,” he said.

“This is about projecting power right into China’s doorstep, it’s not about protecting Australia.”

Press PLAY below to hear why the Greens are object to the mega submarine deal

Details of Australia’s huge $368 billion submarine deal revealed