A Sanctuary No Longer? Examining the Defense Department’s Prioritization of the Homeland

A decade ago, Chairman of the Joint Chiefs of Staff General Martin Dempsey declared, "Our homeland is not the sanctuary it once was." Five years later, in 2018, the National Defense Strategy codified this sentiment: "It is undeniable that the homeland is no longer a sanctuary." This statement has subsequently become the rallying cry of those demanding a refocus on defending the U.S. homeland and an accepted premise for reimagining the Defense Department's role inside the United States. But has the United States really lost its sanctuary status?

The claim that the homeland is no longer a sanctuary has morphed into a potentially misleading mantra with many possible meanings. As a result, it is more important than ever to distinguish between a range of different threats. The homeland is hardly more vulnerable to a missile strike or land invasion today than it was at the height of the Cold War. Instead, a recent technological shift has made U.S. infrastructure more vulnerable, directly impacting U.S. military power projection. Large movements across the country, from secured forts to ports of embarkation, present a tempting target for any adversarial nation interested in disrupting the U.S. military through difficult-to-attribute unconventional or nonkinetic means. At the same time, these disruptive technologies provide adversaries the tools to erode the American way of life, sowing chaos without openly "attacking" the homeland. It is in this specific context that the United States is no longer a sanctuary.

This threat shift has strategic implications. The technological revolution of nonkinetic means provides adversarial nations new tools to weaken the United States by slowing military response times in support of crises, introducing chaos into a generally stable economy, and fanning the flames of controversial domestic debates. Stated another way, if nations like Russia or China aim to supplant the United States in the international system, the proliferation of nonkinetic options provides a path for them to win without fighting.

A Turn of Phrase

With the U.S. focus shifting away from Iraq and Afghanistan and back to near-peer threats like China and Russia, the emphasis on defending the homeland has intensified significantly. While the "Global War on Terror" may have been touted as a means to keep America safe (a controversial concept), its design was to address threats where they originate, to play the away game. Therefore, this shift is effectively a transition from the defend-forward mindset. While the United States will always maintain a forward presence with basing and alliances — working to keep the fight abroad — this new mindset acknowledges that America is vulnerable, a paradigm shift that forces the U.S. military to adapt to a new reality.

This was the essence of General Dempsey's 2013 remarks. For a conventional threat, he contended that "middleweight militaries now have intercontinental ballistic missiles." In the nonkinetic realm, he highlighted the rise of cyber in a military context. Though still an emerging capability at the time, Dempsey argued that "cyber has reached a point where bits and bytes can be as destructive as bullets and bombs." With these thoughts in mind, he concluded that "our homeland is not the sanctuary it once was."

Two pieces of context are crucial for understanding Dempsey's remarks. First, he assessed vulnerability with reference to an active conflict. In examining a future war, he noted that if the United States is "engaged in a conflict virtually anywhere in the globe there is likely to be some effect in the homeland." This coupling of conflict abroad and vulnerability at home is critical to understanding the role of any potential enemy attack — lethal or nonlethal. Second, these comments emerged amongst a budgetary battle that did not favor the Defense Department. As a result, this vulnerability rhetoric fits a historical narrative of exaggerating threats to secure funding or bolster support. A similar argument could well be made today concerning China, given the U.S. withdrawal from Afghanistan and the U.S. military's limited role in the Middle East. However, the department's continued and consistent prioritization of the homeland challenges that line of reasoning, highlighting the threat in times of both growing and shrinking budgets.

More recently, in 2018, the National Defense Strategy reinforced the linkage between an attack on the United States and an active conflict: "During conflict, attacks against our critical defense, government, and economic infrastructure must be anticipated." In contrast to 2013, the Defense Department was not facing any budgetary constraints at this time — quite the opposite. Even while the Pentagon was confronting the Islamic State and preparing for the rise of China, the homeland remained a priority, culminating in the 2022 National Security Strategy and the 2022 National Defense Strategy.

Sanctuary!

In the context of homeland defense, sanctuary can be understood by examining the scope of a conflict. Established boundaries — informal and formal — are often present in warfare. Crossing these boundaries could lead to war escalation, loss of allies, reduced public support, or similar consequences.

Three examples of this type of sanctuary stand out for the United States. First, the U.S. military avoided conducting operations or strikes on mainland China during the Korean War for fear of escalation. Second, North Vietnamese fighters would retreat into Laos and Cambodia during the Vietnam War, believing the United States could not follow. While the United States conducted limited cross-border operations into Cambodia, these actions brought criticism from U.S. voters and Congress. Notably, these actions were eventually a factor in the passage of the War Powers Act, which was "designed to limit the U.S. president's ability to initiate or escalate military actions abroad."

The third example — less tangible but more applicable to homeland defense — is the great power sanctuary of the Cold War. While the United States and the Soviet Union regularly engaged in international actions often directed against the interests of the other (arming the Afghans in the 1980s, for example), the homelands of both states were "off limits" for fear of nuclear escalation. This did not mean the threat did not exist — think of the Cuban Missile Crisis — just that the deterrence model held. Although the Cold War is over, this concept of sanctuary largely remains. Even as the United States openly provides Ukraine with advanced weapons systems to fight Russia, President Joe Biden told reporters that the United States is "not going to send to Ukraine rocket systems that strike into Russia."

What Changed?

So, what changed? The answer lies in the increasing threat of nonkinetic attacks, fueled by a technological revolution and the yet-to-be-seen implications of emerging technologies like cyber, artificial intelligence, and machine learning.

Kinetic attacks are overt acts like military invasions or missile strikes. While a land invasion in North America seems highly unlikely, a missile strike has been a credible threat for decades. Still, long-range missile proliferation is nowhere near as far along as some pundits may claim. Outside of allies like France and England, only Russia and China have a proven capability to strike the U.S. homeland with a missile launched from their territory. While North Korea appears to have recently joined this list, and nations like Iran aspire to do the same, the list remains incredibly small. Advancements in cruise missile technology, hypersonic flight, and varying delivery platforms do complicate this situation and increase the threat. But while this increased threat should be addressed, its nature is not new. The U.S. Navy has been posturing against adversary ships since the Cold War. The U.S. Air Force has a long history of interdicting any foreign aircraft approaching U.S. airspace, limiting how an enemy could use these missile technology advancements.

Moreover, as the Defense Department stated in the 2022 Missile Defense Review, the "United States will continue to rely on strategic deterrence — underwritten by a safe, secure, and effective nuclear arsenal" in order to meet new missile threats. This has been the foundation of U.S. missile policy since these weapons started proliferating globally. Theoretically, the United States has been vulnerable to a missile attack for decades, but at an extremely high cost to the attacker. Consequently, unless a future conflict was with one of these other powers and their "sanctuary" was already violated, it is unlikely an adversarial nation would escalate the conflict with a kinetic attack on the U.S. homeland. The Army reached a similar conclusion in its recent publication of Field Manual 3-0, Operations, writing that "while a conventional attack on U.S. forces conducting operations during competition is unlikely, the greater the perceived danger to their vital national interests, the greater the chance a peer threat will contest U.S. military force projection." Therefore, the status quo that has generally established mutual deterrence between great and rising powers remains unchanged, regardless of recent technological advancements.

While an overt attack remains unlikely, a nonstate attack is a distinct possibility. This includes operations conducted by nonstate actors like terrorist organizations, criminal organizations, and even covert actions by a state seeking deniability. While U.S. geography makes the nation less vulnerable than its European counterparts, few would categorize the United States as a "sanctuary" from this type of attack. As shown on September 11, the United States probably lost this sanctuary status long ago. But even if technological advancements increase the number of these attacks, this does not equate to a fundamental shift that requires reimagining the nature of homeland defense.

Nonkinetic attacks, however, are different. While bits and bytes have not yet proved as damaging as bullets and bombs, nonkinetic weapons have shown their relevance. From the STUXNET cyber attack to Russia's use of electronic warfare in its 2014 Ukraine invasion, they foreshadow a different kind of warfare. If, for example, the United States found itself in a conflict against China, Beijing could conduct a cyber attack to slow America's flow of forces from its forts to a port. This would not only disrupt U.S. military operations, but it would also cost the nation money and credibility. Equally important, this nonkinetic approach can target the homeland nonmilitarily, impacting U.S. infrastructure. Suppose such an attack temporarily knocked out power in a major metropolitan city, shut down port operations at a critical time, disrupted flights at an international airport, or perpetuated false and dangerous messages across numerous social media platforms. This would damage the nation economically, create chaos within the population, and sow distrust in the government.

A further challenge is that these nonkinetic means offer deniability, as highlighted by the U.S. Army Operations Field Manual. At times, a cyber attack may go unnoticed or be incredibly difficult to attribute. Moreover, even when the culprit can be identified, retaliating may still require the United States to convince allies and the public. This in turn may mean revealing classified sources and methods that would be damaging to the United States if exposed. And even then, the perpetrator could pin the actions on an individual or criminal element, publicly denouncing what occurred and denying any state involvement. In the example above, China could deny any involvement and even potentially arrest individual perpetrators if identified to enhance its international narrative. As a result, these types of attacks, coupled with deniability at the international level, throw a wrench into the status quo deterrence model.

Washington can do a great deal by way of "attribution diplomacy" in order to more credibly threaten retaliation for nonkinetic attacks. But despite this, the current technological revolution will still allow hostile nations to act against the United States without inflicting casualties and with a reduced potential for attribution. With no "rally around the flag" from an overt attack and a politically fraught debate about attribution, the United States would struggle to follow through on threats of retaliation.

Conclusion

In short, whether the United States has really lost its "sanctuary" status depends on the type of attack you’re talking about. While countries like Russia and China can attack the United States directly, they are no more likely to do so now than they have been for decades. Additionally, although some nations may boast about their long-range strike capabilities, the list of nations capable of invading or conducting a strike on the U.S. homeland is small and full of allies. Furthermore, while nonstate attacks are becoming easier and potentially more likely, there is not now, nor has there been for generations, a sanctuary from a terrorist/criminal organization or state-sponsored covert action.

Yet the risk of a state-sponsored but deniable nonkinetic attack on the homeland as part of a broader conflict is growing. The U.S. Army has acknowledged that this threat "extends beyond directly targeting unit personnel and equipment," conceding that military operations rely "on various interdependent infrastructures, the majority of which it does not own or operate." Consequently, such actions affect more than a military deployment timeline. While a nonkinetic attack may drastically slow a military response to a crisis and frustrate those allies and partners who rely on the United States, it also has the potential to wreak havoc on the American way of life. In this context, the homeland is no longer a sanctuary, and this scoped realization may have strategic implications. By disrupting force flow and changing what equipment is sent abroad or making the U.S. military "late to need" in an international crisis, an adversary may undermine America's role in the international system. At the same time, this type of attack directed at U.S. infrastructure can erode the population's trust in the government, something easily amplified through disinformation tactics and social media.

The homeland should remain a priority. However, there is no new armor or ammunition that can mitigate nonkinetic attacks. Nor will the military prevent a cyber attack by strategically staging its forces nationwide. Moving forward, any Defense Department restructuring or shift in focus should be couched in a threat assessment and address the challenges of the new operating environment. An article in these pages contended that the "United States can reasonably assume some additional risks to confront undesirable adversary cyber behavior." To do so effectively, an Army cyber operations officer recently argued that the United States "should assert a cyberspace border." Beyond this, establishing redundancies in key systems and infrastructure could also reduce vulnerabilities. Ultimately, though, a different approach is necessary, one that appreciates exactly what form of sanctuary has been lost. For the foreseeable future, power projection vulnerabilities and nonkinetic attacks are problems without easy solutions.

Brennan Deveraux is a major in the U.S. Army currently serving as an Army North planner. He is an Army strategist and an Art of War scholar specializing in rocket artillery and missile warfare. He has completed combat deployments to Iraq and the Horn of Africa and has three defense-related master's degrees, focusing his research on military adaptation and emerging technology management.

The views in this article are the author's own and not those of the U.S. Army or the Department of Defense.

Image: Department of Defense