The US military has for years enjoyed a broad technological edge over its adversaries, dominating foes with superior communications and cyber capabilities.
Now, thanks to rapid advances by Russia and China, the gap has shrunk, and the Pentagon is looking at how a future conflict with a "near-peer" competitor might play out.
Air Force Secretary Heather Wilson recently warned that both Russia and China are experimenting with ways to take out the US military's satellites, which form the backbone of America's warfighting machine.
"They know that we are dominant in space, that every mission the military does depends on space, and in a crisis or war they are demonstrating capabilities and developing capabilities to seek to deny us our space assets," Wilson said.
"We're not going to let that happen."
The Pentagon is investing in a new generation of satellites that will provide the military with better accuracy and have better anti-jamming capabilities.
Such technology would help counter the type of "asymmetric" warfare practised by Russia, which combines old-school propaganda with social media offensives and cyber hacks.
Washington has blamed Moscow for numerous cyber attacks, including last year's massive ransomware attack, known as NotPetya, which paralyzed thousands of computers around the world.
US cyber security investigators have also accused the Russian government of a sustained effort to take control of critical US infrastructure systems, including the energy grid.
Russia denies involvement and so far, such attacks have been met with a muted US military response.
- Public relations shutdown -
General John Hyten, who leads US Strategic Command (STRATCOM), told lawmakers the US has "not gone nearly far enough" in the cyber domain.
He also warned that the military still does not have clear authorities and rules of engagement for when and how it can conduct offensive cyber ops.
"Cyberspace needs to be looked at as a warfighting domain, and if somebody threatens us in cyberspace, we need to have the authorities to respond," Hyten told lawmakers this week.
Hyten's testimony comes after Admiral Michael Rogers, who heads both the NSA -- the leading US electronic eavesdropping agency -- and the new US Cyber Command, last month said President Donald Trump had not yet ordered his spy chiefs to retaliate against Russian interference in the 2016 US election.
Russia has also been blamed for the March 4 poisoning of former spy Sergei Skripal and his daughter Yulia, who were found unconscious on a bench outside a shopping center in England.
NATO countries are working to determine when a cyber attack might trigger the alliance's Article 5 collective defense provision, General Curtis Scaparrotti, the commander of NATO forces in Europe, said this month.
NATO "recognizes the difficulty in indirect or asymmetric activity that Russia is practising, activities below the level of conflict," Scaparrotti said.
In 2015, the Air Force opened the highly secretive National Space Defense Center in Colorado, where airmen work to identify potential threats to America's satellite network.
After officials told a local newspaper, The Gazette, that the center had started running on a 24-hour basis, Air Force higher ups grew alarmed that too much information had been revealed.
In an example of how sensitive the issue of cybersecurity now is, the Air Force reacted by putting its entire public operations department on a "stand down" while it reviews how it interacts with journalists.