WASHINGTON (Army News Service) -- The U.S. Army's dominance is in danger when it comes to future warfare, according to senior leaders.While the biggest threat faced by Soldiers on the battlefield in recent wars may have been the improvised explosive device, new emerging threats from cyberspace, electronic warfare, and unmanned aerial vehicles have Army leaders eyeing new tactics across multiple domains.Since the rout of Iraqi forces in Desert Storm 25 years ago, potential foes have found ways to counter how the U.S. military wages war within an air/land concept, said Gen. David Perkins, commander of the Army Training and Doctrine Command."They've gone to school on us ever since then, while we've been doing all kinds of important work for the nation and the world," Perkins said during a panel discussion at the Association of the U.S. Army's Annual Meeting and Exposition Oct. 4.In Ukraine, Russia and its proxy forces used cyberattacks and electronic warfare equipment to jam communication networks, while using unmanned aerial vehicles to set up artillery fires, and advanced air defense missiles to gain air superiority without airplanes.On the other side of the globe, the Chinese military is using disputed islands in the South China Sea to influence maritime missions."They are fracturing our way of war by using other domains," Perkins said. "We can't do it with two domains. Air and land are not enough."The Army of the future must be prepared for multi-domain battle, a battle taking place not just in the domains of air and land, but also in the domains of sea, space, and cyberspace. Such an army would employ infantrymen with cyberspace skills, innovative air defense systems to deter enemy aircraft, and even ground-to-ground missiles to target enemy ships."We're going to sink ships, and we're definitely going to have to dominate the airspace above our units from hostile air or missile attack," Army Chief of Staff Gen. Mark Milley said, during another discussion at the conference. "This is going to require sophisticated air defense capabilities that are not currently in our unit inventories."The next 25 years on the battlefield, he predicted, will be nothing like the last 25, or even the last 10."The culminating challenges we face in the changing character of war is unlike anything our current force has ever experienced in intensity and lethality," he said.It's still too early to know when the multi-domain concept will be completed, said Perkins, adding that the air/land concept took eight years to be implemented after it first was introduced in 1973. While he doesn't expect multi-domain to take that long, he does expect that getting the other services involved will be a long process."This is pretty much the beginning of a new way of thinking," he said, noting that talks with leaders from the other services have already begun, with more to come. "This takes a lot of collaborative discussions."Marine Corps Commandant Gen. Robert Neller is one of the leaders taking part in these joint talks. He and the Army chief of staff, he said, are looking to reinvigorate the Army-Marine Corps Board to discuss ideas and requirements."We've been shoulder-and-shoulder on multi-domain battle and land concepts," Neller said at the panel discussion. "We can't afford to waste any resources on duplication when it's not necessary. We see the problem the same way; we have the same conclusions."As new ideas driven by the multi-domain concept are introduced, some Army programs may be altered or cut to make room. Perkins said they will evaluate Army programs to see if they match with future plans or if the funding would be better reinvested in another priority."We're looking internally in the Army," he said. "Do we have the right priorities out there? That is not an easy process. It takes a lot of thoughtful analysis."Such changes could drastically affect funding across the service, which Perkins said would be an ongoing process over time."Once we gain clarity of where we're going, it'll make it easier for Congress to understand what we want to use the money for," he said.Additional funding might come from a new Defense Department warfighting fund."We're confident that the Army can get after it, but we also know that resources are tight," Deputy Defense Secretary Robert Work said at the event. "That fund is designed to let the Army get after it."The multi-domain battle concept would fall under Work's Third Offset Strategy, a Department of Defense-wide plan, the implementation of which will likely be heavily influenced by human-machine systems.While autonomous assistance from technology will play a role on the future battlefield, Soldiers and other military members will still be making the decisions."We will use machines to empower the human, not vice versa," Work said. "This is not about Skynet and Terminator, this is about Ironman. This is machines helping the human achieve effects."With the multi-domain concept rooted in a force of trained and confident Soldiers, the U.S. Army will have an advantage over enemies working with similar technology, according to Perkins."It's hard to steal training and leadership," the general said. "You can't hack into it, and it won't fit on a thumb drive. So, we think that is our asymmetric edge."