U.S. Military Leadership Warns Future Conflicts Will Span From the Seabed to Cislunar Space

The landscape of modern warfare is expanding at an unprecedented rate, moving far beyond traditional terrestrial boundaries into the vast expanse of the cosmos. Speaking at the Air & Space Forces Association’s Air, Space & Cyber Conference in National Harbor, Maryland, high-ranking defense officials laid out a stark vision for the future of national security. According to the nation’s military leadership, future conflicts will no longer be decided solely on land, at sea, or in traditional airspace; instead, they will encompass a vastly extended domain stretching from the deepest trenches of the ocean floor all the way out to cislunar space—the region encompassing Earth, the moon, and the space between them.

The remarks, delivered by Chairman of the Joint Chiefs of Staff Gen. Dan Caine and U.S. Space Force Chief Gen. Douglas Schiess during the mid-September conference, highlight a profound strategic shift. As geopolitical competition moves into the final frontier, the United States military is actively preparing to deter, fight, and win in contested environments that were once considered the exclusive domain of scientific exploration and peaceful international cooperation.

The Expanding Operational Horizon

Gen. Caine’s keynote address painted a picture of a future battlefield characterized by complexity and extreme distance. For decades, American military doctrine focused on regional dominance, projecting power across oceans and managing localized conflicts. However, rapid advancements in aerospace technology, satellite infrastructure, and lunar exploration have forced a radical rethinking of operational boundaries.

"Today’s modern battlefield operates from the seabed to cislunar space," Gen. Caine stated during his address.

Cislunar space—the massive orbital highway extending roughly 240,000 miles from Earth to the lunar surface—is rapidly emerging as a critical geopolitical and strategic chokepoint. With major spacefaring nations planning permanent outposts on the moon within the next ten to fifteen years, the area is transforming from a scientific frontier into a vital operational domain.

Military planners have noted that whoever establishes a permanent presence on the moon, particularly near the resource-rich south pole, will effectively set the rules of the road for future space commerce, navigation, and defense. The lunar south pole is of particular interest due to its suspected vast reserves of water ice, which can be harvested to sustain human life and processed into rocket propellant, effectively turning the moon into a strategic fueling station and staging ground for deep-space operations.

A Chronology of Escalating Competition in Space

The militarization and strategic contestation of Earth’s orbit and cislunar space did not happen overnight; it is the culmination of decades of technological progress and shifting geopolitical dynamics.

• 2007: China conducted a successful anti-satellite (ASAT) missile test, destroying one of its own defunct weather satellites in low Earth orbit. This event created thousands of pieces of long-lasting space debris and served as a wake-up call to Western defense planners regarding the vulnerability of orbital assets.
• 2014–2019: Both Russia and China began deploying specialized "inspector" satellites and maneuvering spacecraft capable of shadowing foreign satellites, raising concerns about orbital espionage and potential on-orbit interference.
• 2019: China achieved a historic milestone by landing the robotic Chang’e 4 mission on the mysterious far side of the moon, demonstrating advanced communication and navigation capabilities in deep space.
• December 2019: Recognizing the growing vulnerability of space-based assets, the United States formally established the U.S. Space Force as the nation’s first new independent military branch since 1947.
• 2024: China’s Chang’e 6 mission successfully retrieved soil and rock samples from the far side of the moon and returned them to Earth, further cementing the nation’s deep-space capabilities.
• September 2026: During the Air, Space & Cyber Conference, top U.S. military leaders openly acknowledged the operational realities of cislunar warfare and the deployment of active defensive space weapons.

The Reality of On-Orbit Defense

While Gen. Caine focused on the strategic breadth of global contested environments, Gen. Douglas Schiess, head of the U.S. Space Force, provided concrete insight into how the military is protecting these vital assets closer to home. In a candid admission during his conference address, Schiess confirmed that military personnel—officially known as Guardians—are actively operating defensive weapons in Earth orbit.

"Let me be crystal clear: Today, guardians operate on-orbit weapons that can defend the joint force against space-enabled attacks," Schiess said.

While defense officials have historically maintained a veil of secrecy around offensive and defensive space capabilities, Schiess’s remarks marked a notable shift toward strategic transparency. He indicated that these orbital systems are primarily electromagnetic rather than kinetic in nature. Unlike kinetic weapons—such as missiles designed to physically shatter targets—electromagnetic systems are built to neutralize enemy threats through jamming, blinding, or temporarily disabling adversary satellites.

This approach minimizes the risk of generating devastating space debris fields, which can pose an indiscriminate hazard to commercial satellites, scientific instruments, and crewed spacecraft alike. Past destructive ASAT tests conducted by other nations have generated extensive debris clouds that threaten the global commons of low Earth orbit, prompting international condemnation and a push for responsible norms of behavior in space.

Strategic Implications and the New Moon Race

The public acknowledgment of orbital weapons and the designation of cislunar space as a potential battlefield underscore a fundamental shift in modern defense strategy: space can no longer be regarded as a sanctuary.

For generations, the U.S. military has relied on uncontested access to space for communications, global positioning systems (GPS), missile warning architectures, and intelligence gathering. However, peer competitors like China and Russia have developed robust counter-space portfolios designed to deny, degrade, or destroy these critical advantages.

"Future conflicts will demand that we operate without the assumptions of uncontested access, secure rare areas or uninterrupted or uncontested sustainment," Gen. Caine warned. "Our task, my friends, is to adapt right now, so the joint force is prepared to fight, endure and win in global contested environments, from the seabed to cislunar space."

To meet these emerging threats, the U.S. military is prioritizing domain awareness, resilient satellite architectures, and rapid technological adaptation. The Space Force is tasked with maintaining an unbroken chain of data and situational awareness across millions of miles, ensuring that ground and naval forces can project power globally even when traditional communications links are targeted by electronic warfare or cyberattacks.

Conclusion: Preparing for the Next Frontier

As the boundary between science fiction and geopolitical reality continues to blur, the United States and its international rivals are locked in a silent, high-stakes competition that extends far beyond Earth’s atmosphere. The declarations made at the National Harbor conference signal that national security apparatuses are fully pivoting to address the realities of multi-domain warfare.

Whether cislunar space remains a peaceful scientific frontier or becomes an active theater of geopolitical friction will depend heavily on the establishment of international norms, deterrence strategies, and technological readiness. For now, American military leadership has made its stance unmistakable: to secure peace on Earth, the nation must be fully prepared to defend its interests from the ocean floor to the surface of the moon.