Major General Susan Coyle's life on the road began long before she commanded Australia's forces in the Middle East, or led a task force in Afghanistan, or even before she joined the army as a 17-year-old.

She was born on a remote posting: in Kyogle in northern NSW.

"It was a transient childhood," says Major General Coyle, who from July will be a three-star general and the first woman to lead what the military calls a "war-fighting domain".

"My father worked for the Water Resources Commission, within the NSW government. We would move from dam site to dam site and once the wall was built to capture the water, our house would get packed up onto two trucks, and we'd go to the next dam site.

It may explain her later choices: During 36 years with the army she's shifted 28 times, accompanied often but not always, by her husband Mark, who also serves in the army, and their three children.

"I was very conscious for my children — once they hit high school, we tried to have stability. And so one of us would be based in Canberra, or if necessary, my son went into boarding school for a couple of years," she says.

"It's a choice – you get great experiences from living abroad or living in other states."

Overseeing new areas of conflict

In July, Major General Coyle will be promoted to lieutenant general – the army's second-highest rank – and will begin her new role as chief of joint capabilities. In that role she'll be in charge of the ADF's cyber and space commands, as well as information warfare.

It's a vital role, says retired major general Gus McLachlan.

"Commander, joint capabilities is really the fourth of our service chiefs. We have traditional domain chiefs for navy, army and air force, and we've had them for hundreds of years. The fourth chief is now the domains that cover the new areas of human conflict," he said.

"She represents a transition in the officer corps of the army," says Mr McLachlan.

"The 21st Century domains of space, cyber, information warfare requires a new generation of officers who've come through. The digital natives who understand that environment."

Information warfare "is about changing the will of the enemy and deterring them from fighting", says Major General Coyle.

It encompasses propaganda used by both sides in the Russia-Ukraine war.

"[An] example is the fake news broadcast where a video has been tampered with that shows Zelensky telling his troops to put down their weapons," Major General Coyle says.

"Or one from Ukraine … where they did a Russian pamphlet, and it showed Russian soldiers how to defect."

Space, the next frontier?

She's also in charge of Australia's embryonic space command. As a captain in the army, she trained in the United States to navigate and control satellites.

"We're building trades to be space experts, and building training institutions," she says.

"So we're looking at what's up in the sky … what satellites are ours or our allies? What are commercial ones that we have to protect, and what are other satellites up there that we're not aware of that may be adversaries' satellites, and what are they doing?" she says.

Mr McLachlan says some people believe that the next major conflict will start in space.

"One of the things that might signal future conflict is when there are attacks on geostationary satellites," he says.

"Things like GPS … Google Maps on our phone relies on that, but so too does encryption, which means our banking processes, all of those require what we call precision navigation and timing from space. So Australia needs an understanding of what is happening in space."

Fighting on new frontiers comes with old-fashioned problems, like retaining highly-skilled workers.

"Ultimately, we just have to create something where people want to be a part of it and I think once people get in the door, they love it.

"Then it's up to us as leaders to make sure that they feel valued, empowered and want to stay for as long as they choose to."

The Department of Defence wants to increase its workforce to over 101,000 by 2040 – from the current workforce of around 60,000, but is struggling to maintain even that level.

Keeping staff requires flexible working arrangements, according to Major General Coyle.

"I think different people have different reasons for staying or leaving," she says.

"And you know, for me, it's about leaving the door open.

"If someone chooses to leave, we let them go, and then we invite them back in six months or 12 months, once they've gotten whatever it is out of their system, or for those that need to transition we farewell them and thank them for their service."

'Lots of really good women coming through'

Major General Coyle says the army has changed for the better since she was a young soldier and was worried about taking her maternity leave entitlements.

"I was in my 20s when I had my kids. And at that time, I didn't think if I took an extended break I'd come back," she says.

"I was at that stage in my career where I was so motivated to serve. And I also thought at the time that I wouldn't be seen as credible if I took a long break. And I'm really pleased to say that these days that is not the case.

When Major General Coyle joined the military she says just 10 per cent of personnel were women, and the highest ranked female soldier was a colonel. Now, she's about to become one of three female three-star generals.

"I went to the Defence Academy with the other ladies. I've known all of them my whole life," she says.

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