There are several hundred Australian defence personnel deployed in Iraq. The Commander in Chief of the nation controlling their action has just told Iraqis that the US should have taken their oil after invading their country in 2003. He then left the door open to have another crack.

This wasn't a second-hand report of a private conversation: it was an in-depth one-on-one interview with America's ABC News' 20/20 program. President Trump repeatedly said the US should have taken or "kept the oil."

"We should've taken the oil," he told ABC anchor David Muir. "And if we took the oil you wouldn't have ISIS. And we would have had wealth."

I've just watched the program. I think it is the most worrying interview by any politician in my lifetime. It was scary.

This was not Trump running off at the mouth during an election campaign or the disappointing repetition of a campaign speech at his inauguration. It was the considered public pronouncements of the President and Commander in Chief of the United States.

Trump's statements are a worry on a number of fronts, from his persistent paranoia about the presidential popular vote to beginning to dismantle US government involvement in climate science, but the oil section of the interview should bring into question the sustainability of the Australian alliance. The kindest thing that can be said about the Commander-in-Chief is that he is a loose cannon – and that is being very kind.  In his talk of security issues, "madman" would also fit.

When Muir countered the "should have kept the oil" line with the view of critics that it would break all international law, Trump dismissed such critics as "fools".

And he would not backtrack from the report that he had suggested the US could yet seize Iraq's oil.

"Well, don't let it get your attention too much because we'll see what happens. I mean, we're gonna see what happens. You know, I told you and I told everybody else that wants to talk when it comes to the military I don't wanna discuss things," he said, repeating his frequent critique of the military foreshadowing the assault on Mosul in Iraq.

"I don't wanna do a lot of talking on the military. I wanna talk after it's finished, not before it starts."

Australia's defence policy is based upon being part of the American military machine. We are paying some tens of billions of dollars more than necessary for submarines because we want large, long-range subs that could operate in the South China Sea as part of American policy. We have chosen to be part of America's "pivot to Asia" – the euphemism for American policy to encircle and limit China.

In view of who now commands US foreign policy and its military forces, that doesn't look like money well spent.

Here is a taste Iraq section of the 20/20 interview. Only read the full transcript if you're feeling strong.

DAVID MUIR: You brought up Iraq and something you said that could affect American troops in recent days. You said, "We should've kept the oil but okay maybe we'll have another chance." What did you mean by that?

PRESIDENT TRUMP: Well, we should've kept the oil when we got out. And, you know, it's very interesting, had we taken the oil, you wouldn't have ISIS because they fuel themselves with the oil. That's where they got the money. They got the money from leaving -- when we left, we left Iraq, which wasn't a government. It's not a government now.

And by the way, and I said something else, if we go in and do this. You have two nations, Iraq and Iran. And they were essentially the same military strength. And they'd fight for decades and decades. They'd fight forever. And they'd keep fighting and it would go -- it was just a way of life. We got in, we decapitated one of those nations, Iraq. I said, "Iran is taking over Iraq." That's essentially what happened.

DAVID MUIR: So, you believe we can go in and take the oil.

PRESIDENT TRUMP: We should have taken the oil. You wouldn't have ISIS if we took the oil. Now I wasn't talking about it from the standpoint of ISIS because the way we got out was horrible. We created a vacuum and ISIS formed. But had we taken the oil something else would've very good happened. They would not have been able to fuel their rather unbelievable drive to destroy large portions of the world.

DAVID MUIR: You've heard the critics who say that would break all international law, taking the oil. But I wanna get to the words ...

(OVERTALK)

DAVID MUIR: ... that you ...

PRESIDENT TRUMP: Wait, wait, can you believe that? Who are the critics who say that? Fools.

DAVID MUIR: Let, let me ...

PRESIDENT TRUMP: I don't call them critics. I call them fools.

DAVID MUIR: ... let me talk about your words ...

PRESIDENT TRUMP: We should've kept -- excuse me. We should've taken the oil. And if we took the oil you wouldn't have ISIS. And we would have had wealth. We have spent right now $6 trillion in the Middle East. And our country is falling apart.

(OVERTALK)

PRESIDENT TRUMP: Our roads -- excuse me. Our roads, our bridges, our schools, it's falling apart. We have spent as of one month ago $6 trillion in the Middle East. And in our country we can't afford to build a school in Brooklyn or we can't afford to build a school in Los Angeles. And we can't afford to fix up our inner cities. We can't afford to do anything. Look, it's time. It's been our longest war. We've been in there for 15, 16 years. Nobody even knows what the date is because they don't really know when did we start. But it's time. It's time.

DAVID MUIR: What got my attention, Mr. President, was when you said, "Maybe we'll have another chance."

PRESIDENT TRUMP: Well, don't let it get your attention too much because we'll see what happens. I mean, we're gonna see what happens. You know, I told you and I told everybody else that wants to talk when it comes to the military I don't wanna discuss things.

I wanna let -- I wanna let the action take place before the talk takes place. I watched in Mosul when a number of months ago generals and politicians would get up and say, "We're going into Mosul in four months." Then they'd say, "We're going in in three months, two months, one month. We're going in next week."

Okay, and I kept saying to myself, "Gee, why do they have to keep talking about going in?" All right, so now they go in and it is tough because they're giving the enemy all this time to prepare. I don't wanna do a lot of talking on the military. I wanna talk after it's finished, not before it starts.