Yet so many decisions to go to war have been political - for political, rather than national interests.

It has always struck me as particularly odd, given the importance of such a decision, that in Australia the decision can be taken by the prime minister alone.

Although he/she may take advice from military, security, and intelligence personnel, and/or may take it to cabinet, there is no explicit requirement in our constitution or in defence legislation for them to do so.

Similarly, there's no requirement for public debate before the decision is taken, either in the Parliament or across the broader community.

Surely it's time to require at least significant parliamentary scrutiny and debate, with effective engagement with the community, to ensure that any decision is in the national interest?

In World War I, Australia - legally part of the British Empire - was at war as soon as the British government made its declaration.

Although cabinet formally approved placing our navy and troops under British command, the engagement of Parliament waited the return of the writs from a double dissolution election, with the Governor-General's speech calling for the belated ratification of the war expenditure.

Similarly with World War II, the Menzies government felt that it really didn't have a choice - Britain was at war, so too Australia.

The decision was simply gazetted. A parliamentary debate ensued a few days later when Robert Menzies delivered a ministerial statement.

The Opposition criticised Menzies for failing to outline his intentions and detail his general principles in making the commitment, but the motion passed in the Senate on the voices.

On the Korean War - having already placed naval and air force assets at the disposal of the US, on behalf of the UN Security Council - Menzies simply made a statement to the house and was supported by the Opposition, with no division in either house.

Australia drifted into the Vietnam War, supporting South Vietnam in response to the "domino theory", and the US, both to keep them engaged in south-east Asia, and hopefully ensure their support for our future security.

The drift began with a commitment to provide "military instructors", without any parliamentary debate, to more formal, sizeable commitments of troops in response to formal requests from the South Vietnamese government.

The Opposition said "we oppose it firmly and completely", with the house dividing along party lines. Initial public support for our engagement waned through the early 70s, with serious division over conscription.

On the Gulf War, Bob Hawke and I agreed on an initial, modest naval commitment.

Subsequently, there was a parliamentary debate producing bipartisan support for our participation in UN-sanctioned multi-national force.

Our engagements in Afghanistan and Iraq were mostly driven by the emotion of 9/11, and more by John Howard's political interests, wanting to be "deputy sheriff" to George W Bush, than our national interest.

On Afghanistan, Howard pledged support for a US military response before it had been requested.

He also pushed support for the unsanctioned, US-led invasion of Iraq, aiming to destroy weapons of mass destruction and achieve regime change from Saddam Hussein.

The Opposition opposed it. No such weapons were found, and the war drifted on for some six years.

Against this background, the politics being played by Peter Dutton and Home Affairs secretary Michael Pezzullo - wanting to place us on a "war footing", to hear the "beating drums of war" and to recognise the "possible Chinese military action over Taiwan" - should be of particular concern.

Is this the beginning of another drift into a war that may not be in our national interest? Are they serious, or is it just another Morrison distraction? It raises important questions and has serious consequences.

Should we really be considering a war with China?

Their military spending is some 10 times ours - 2 per cent of GDP won't cut it.

Where is our national interest in a Taiwanese conflict?

Although China tries to force the world to accept its One China Policy, isn't this more an internal issue for the Chinese?

How does the government figure China will react to these statements? Especially as it has already called us out for doing Trump's bidding on China's "developing country" trade status; calling for the investigation of the "Wuhan virus"; blocking Huawei 5G: blocking Victoria's Belt and Road initiative: reviewing a host of other Chinese business and asset purchases in Australia; and so on.

We need much more maturity and responsibility on this issue.

John Hewson is a professor at the Crawford School of Public Policy, ANU, and a former Liberal opposition leader.