The Army's top leader says soldiers will be operating in extremely austere conditions and fighting amid dense urban populations under constant threat of electronic surveillance that can make it dangerous to stay in one place for long.

This is the future of ground warfare, but a future that is taking shape now and presenting the Army with unprecedented challenges, Army Chief of Staff Gen. Mark Milley said Tuesday in a keynote address at the Association of the U.S. Army meeting in Washington, D.C.

"There is no doubt in my mind that a combination of geopolitical and societal change will result in the most significant and profound change in war we have ever seen in history," Milley said.

A series of rising factors will have a significant impact on what the US Army will face, and what it will have to do to prepare. Those include a shifting international order, Russia and China emerging as aggressive forces, increasingly invasive cyber threats, and global climate change that will make natural resources more scarce to the point that the potential for armed conflict over those resources is "very, very real," Milley said.

The Army is focused on imagining the potential scenarios to play out, he said.

"We are on a serious and deliberate campaign of learning to figure it out, and we need to learn it fast," Milley said.

He envisions a near future in which soldiers deploy in small, highly mobile, constantly moving groups that use every type of cover and concealment. Luxuries like fast food and showers may be out of the picture; purifying their water will be routine.

After a year of studying the challenges ahead, Milley said the Army can expect:

-          "Fundamental, profound" change in warfare and how wars are fought in terms of weapons and doctrine, a change that has begun and will be evolutionary.  

-          Forces must be capable of operating in a multidomain environment. The Army will sink ships and dominate air space above operating areas, Milley said. Land based forces will have to penetrate denied areas. Expectations will be the "exact opposite of what we've done for the last 70 years," he said.

-          Shifting geopolitical concerns around the world will have a significant impact on how the Army plans and operates. Milley cited the international order undergoing significant stress, massive numbers of people moving from one country or region to another, urbanization around the world leading to the certainty that future wars will be fought in cities rather than rural areas, and climate change resulting in diminished fresh water around the world.

-          "The mother of all technologies," artificial intelligence, or AI, in machines that can learn and adapt, potentially creating ethical challenges for leaders. Other capabilities, such as pervasive intelligence, surveillance and reconnaissance, will mean that anyone can be watched nearly anywhere. And anyone stationary for long can be hit in an attack.

-          The overmatch the US has had is eroding quickly, and the US is challenged in every domain.

To prepare for the future, the Army must grow leaders that are prepared to operate independently, should technology fail and communication with higher headquarters become impossible.

"We must develop leaders who have incredible character under intense pressure … who are trusted to do the right thing in an emotionally charged environment," Milley said.

Those leaders would be responsible, empowered and accountable for the results achieved in operations. They will have to be prepared for austere, and even miserable, conditions.

"We may have to learn to read a paper map again," he said.