WASHINGTON, D.C. — The U.S. Air Force considers “maintaining space superiority” one of its “core missions,” high-ranking American military officials told lawmakers Wednesday, warning that “space is now a warfighting domain.”

In jointly written testimony submitted to the Senate Armed Services Subcommittee on Strategic Forces Wednesday, top officials in charge of America’s military space program told lawmakers:

For decades the United States has enjoyed unimpeded freedom of action in space. This benign environment allowed us to operate satellites for intelligence collection, missile warning, weather monitoring, communications, and precision positioning, navigation, and timing in support of all military operations for all of the services, without thinking about how to protect these systems. That environment no longer exists. Space will be contested in any conflict… Clearly, freedom to operate in space is not guaranteed. In fact, space is now a warfighting domain, similar to the more familiar air, land, and maritime domains our men and women are fighting in today. We must ensure the reliability of our current systems and we must modernize. Our modernization will focus on our ability to deter potential adversaries, and to fight in a contested, degraded, and operationally limited environment should deterrence fail.

The warnings came from Heather Wilson, secretary of the U.S. Air Force; Gen. David Goldfein, chief of staff of the Air Force; Gen. John Raymond, commander of U.S. Air Force Space Command; and Lt. Gen. Samuel Greaves, commander of the U.S. Air Force Command’s Space and Missile System Center.

“Our potential adversaries understand the advantage we derive from space and view our reliance on space as a vulnerability they can exploit,” they noted. “Near-peer competitors will offset any U.S. military advantage derived from our space systems and continue to pursue capabilities to degrade or destroy them.”

In its latest World Threat Assessment, issued last week, Director of National Intelligence Dan Coats identified Russia and China as America’s primary rivals in space.

“We assess that Russia and China perceive a need to offset any US military advantage derived from military, civil, or commercial space systems and are increasingly considering attacks against satellite systems as part of their future warfare doctrine,” pointed out the assessment. “Both will continue to pursue a full range of anti- satellite (ASAT) weapons as a means to reduce US military effectiveness.”

“The global threat of electronic warfare (EW) attacks against space systems will expand in the coming years in both number and types of weapons,” adds the DNI. “Development will very likely focus on jamming capabilities against dedicated military satellite communications (SATCOM), Synthetic Aperture Radar (SAR) imaging satellites, and enhanced capabilities against Global Navigation Satellite Systems (GNSS), such as the US Global Positioning System (GPS). Blending of EW and cyber-attack capabilities will likely expand in pursuit of sophisticated means to deny and degrade information networks.”

Russia and China will likely “complete development” of “ASAT weapons” in the next few years, states the assessment.

DNI coats warns, “Russia is developing an airborne laser weapon for use against US satellites. Russia and China continue to conduct sophisticated on-orbit satellite activities, such as rendezvous and proximity operations, at least some of which are likely intended to test dual-use technologies with inherent counterspace functionality.”

For operation and maintenance of space programs alone, the Pentagon has requested nearly a billion dollars for fiscal year 2017 (October 1, 2016 thru September 30, 2017) that does not include hundreds of millions for procurement as well as research and development programs.

“Maintaining Space Superiority (freedom from attack and the freedom to maneuver and attack) is a core USAF mission. It is not just operationally important, it is also a strategic imperative for protecting U.S. and allied capabilities throughout a crisis or conflict,” the high-ranking military officials told senators.

“The Air Force is the lead service for space. Our space systems, including our ground elements, could be the first system attacked in a high-end fight. We are committed to gaining a full understanding of space operations in a contested environment,” they continued.

The U.S. military acknowledges its space policy is facing some challenges.

“In 2017, your Air Force will finalize our family of space warfighting Concepts of Operations, identify our capability gaps, continue our posture transition to increase deterrence, and ensure our force can fight and win a conflict that either starts or extends into space, and strengthen our support to Combatant Commanders,’” testified the officials.

“We are cognizant that the decisive advantage that space brings to military operations has been the deciding factor in every military operation conducted in recent years. Your Air Force remains committed to leading the space enterprise to ensure our joint warfighters can fight and win in every domain,” they added.