Many top defense officials acknowledge that while the nature of war has not and likely won’t change, the character of war is.

This is evident in conflict today and projected battles of the future with a combination of kinetic and non-kinetic effects against militaries and to effect populations using the information space.

Lt. Gen. Vincent Stewart, director of the Defense Intelligence Agency, calls this fifth-generation war.

Does war fighting in the information age still look like two armies clashing on a battlefield – a violent clash between hostile forces each trying to impose their will on the other? In part yes, Stewart said during a keynote address at DoDIIS 2017 in St. Louis Monday. The nature of warfare hasn’t changed. War remains an act of force to compel an adversary – nothing less, but the battlefield isn’t always physical these days.

“All too often we find ourselves fighting warfare in the ways that are not purely kinetic,” he said.

As opposed to specific platforms like the F-35 Joint Strike Fighter, Stewart said for him fifth-generation war is about the fight for information.

Providing a history lesson of sorts, Stewart explained how the first generation of warfare was the mastering of firepower; the second generation was the early modern technology tactics of small units operating independently; the third generation focused on late modern technology leveraging speed, stealth and combined arms; and the fourth generation was post-modern and turned to decentralized warfare such as terrorism.

The fifth generation will be cognitive warfare, he said.

Stewart painted a picture of how fifth-generation warfare might play out using the Russian incursion and eventual annexation of the Crimean peninsula in Ukraine as a case study.

In third-generation warfare the Russians would’ve massed a combined force of armor and air craft seized the peninsula through speed and brute force, he said. In fourth-generation warfare they would’ve engaged in insurgency with decentralized forces striking independent targets to sow fear.

But what they actually did was they shaped the information environment, proclaiming that they would defend ethnic Russians, set the undignified little green men to seize key locations and used information warfare and cyber attacks to cripple communication channels and media outlets. By the time they held the referendum in Crimea, Stewart explained, Ukraine’s decision space was gone. Russia already had controlled the peninsula, all without firing many shots.

Other nations are utilizing the same tactics. China with its island building in the South China Sea Iran with its Quds Force using cyber attacks in Iraq and Syria so to build a sphere of influence in the Middle East.

Fifth-generation war is not just reserved for nation-states. After 16 years fighting the same enemy – violent Salafi jihadists in Afghanistan and around the world, who are inferior to the U.S. in every military way – the U.S. has “failed to bend their will,” Stewart said. Their use of the information space to radicalize young people, to infiltrate and corrupt our information systems has been a wake up call to the rest of the world, he said, adding he doesn’t foresee them stopping anytime soon.

In this new cognitive, information-era conflict, potential adversaries are seeking to disrupt their competitor’s ability to resist and doing it outside the expected forms of battle. Many might not even think they’re at war but adversaries are busy shaping the battlefield and undermining the order one could seek to uphold, he said.

Within that context, Stewart said he believes the U.S. is preparing to fight the last war, meaning wars of the past. “Today we’re largely preparing our network defenses for a peacetime environment or a low intensity conflict against threats like hackers, non-state actors, terrorists or nation states with inferior capabilities to our own,” Stewart, who in June was tapped to be the next deputy director of Cyber Command. “Sometimes I believe that is what we get with our networks. Our network defense tells us very clearly after the fact there’s been a robbery.”

Most networks are simply monitoring the attacks, intrusions and malware after they’ve already done their damage and then it’s too late, he added, asserting this is not a model that works in the age of fifth-generation cognitive warfare.

“What happens when we face a peer competitor our networks will be under immense attack and they will not function like we expect them to,” he asked. “We need resilience, we need reliability, we need redundancy in network defense. Better yet, we need to maneuver our networks against our adversaries.”