In the future, many of the most effective weapons used against the U.S. military are likely to be unseen: electromagnetic waves that disrupt radios or jam global positioning systems, paralyzing units.

This realm of fighting is called electronic warfare, and since the 9/11 attacks it’s been relegated to a lower priority than fighting insurgent groups with precision guided munitions and drones. Now, defense officials say they’re worried that the U.S. military’s ability to counter and wage electronic warfare has atrophied and is lagging behind countries such as Russia and China.

“We don’t have the gear,” Col. Jeffrey Church, the head of the Army’s electronic warfare division, said in a recent interview. “We’re working on getting it, [but] we’re talking years down the road, when our adversaries are doing this right now.”

One place where the United States’ adversaries have displayed their proficiency in electronic warfare is in eastern Ukraine, where the Pentagon has watched Russian forces with a wary eye, gleaning what they can from the country’s reinvigorated military.

“The Russians have worked hard in recent years” in electronic warfare, Gen. Ben Hodges, the commanding general for the Army’s forces in Europe, said during a recent interview. “What they’ve done in east Ukraine and in Crimea has allowed us to study the challenge.”

One Ukrainian special-forces colonel fighting outside of the war-torn city of Donetsk said his men were targeted by an artillery strike after Russian-backed forces located his troops solely by his radio transmissions. The colonel, who for security reasons would identify himself only by his first name, Andrei, said in a recent interview that the radio they had was an American-brand Harris radio. The radio was capable of encrypted communication, but since its output was so much more powerful than the smaller handheld radios the regular Ukrainian troops often carry, the Russian-backed separatists were able to locate the American radio and attack its broadcast site with artillery.

The U.S. Army has a potential tool that would counter the Russians’ techniques, according to Church. Called the Integrated Electronic Warfare system, the three-piece program is meant to be a sort of one-stop shop for the Army’s electronic warfare division. The system is essentially a collection of software, sensors and devices that can be mounted to ground vehicles and drones and carried in troops’ rucksacks and will be able to jam, detect and identify enemy interference. The catch? It isn’t completely funded and has no set year when it will be ready, though one component of the system is slotted to be fielded by the end of 2016, with another due in 2023.

“We’ve been talking about this since 2005,” Church said, referring to one component of the Integrated Electronic Warfare system that was supposed to be ready in 2009 but won’t be in the field until later this year. “There’s these guys that have been looking at really neat pictures of really neat capabilities for years and we still don’t have it.”