As reported by Censor.NET citing The Independent, this was announced by Army Chief of Staff General Mark A Milley at future-of-the-Army panel on Tuesday.
Any future war with Russia or China would be "extremely lethal and fast" and produce violence on the scale not seen for 60 years, according to U.S. generals.
Artificial intelligence and automated weapons systems will accelerate any future conflict, Major General William Hix has warned.
"A conventional conflict in the near future will be extremely lethal and fast," he told a future-of-the-Army panel on Tuesday, Defense One reports. "And we will not own the stopwatch."
"The speed at which machines can make decisions in the far future is likely to challenge our ability to cope, demanding a new relationship between man and machine."
He warned that technological advancements made by Russia and China in recent years had forced the White House to prepare for "violence on the scale that the U.S. Army has not seen since Korea".
The U.S. faces existential threats from modern-states "acting aggressively in militarised competition," Lieutenant General Joseph Anderson, Army deputy chief of staff for operations, plans, and training, told the panel.
"Who does that sound like? Russia?" he asked.
Such a war is "almost guaranteed," Army Chief of Staff General Mark A Milley said at the same event.
Future adversaries could end the U.S.'s traditional air superiority, and anti-access, area-denial capabilities could prevent the Navy from getting near the battlefield.
So "land forces will have to enable sea forces," and the Army "is definitely going to have to dominate the air above our battle space," he added.
The Army will also have to be prepared to engage in cyber warfare, work without space-based communications and precision navigation it has come to take for granted, and fight in a complex urban settings.