Preparing for Simultaneity

The Hon. Dov S. Zakheim

Four years ago, I expressed in these pages my worry that the United States was “not in a position to respond to the prospect of a “triple move” by China, Russia, and Iran.” I raised the prospect of “Eurasian simultaneity”—that adversaries of the United States “would have every incentive to exploit opportunities to change regional and global balances in their favor depending on how distracted the United States became.”[1]

The 2026 National Defense Strategy explicitly acknowledges my concern: “It is only prudent for the United States and its allies to be prepared for the possibility that one or more potential opponents might act together in a coordinated or opportunistic fashion across multiple theaters.” This is an unwelcome development for the US national security community. From the end of the Korean War until its departure from Iraq and, later, Afghanistan, the United States never really had to cope with a two-front war. Indeed, even during the Korean War, when China’s entry in late October 1950 both changed the nature of that conflict and prolonged it, America was not at war anywhere else, though the Cold War was at its height. NATO and the Warsaw Pact confronted each other along the inner German border and the Iron Curtain, but the two sides never actually went to war.

Nevertheless, American defense planners throughout the remainder of the 1950s and into the 1960s continued to postulate a possible two front war against the Warsaw Pact in Europe and communist China in Asia.[2] Even when it became clear after the Cuban Missile Crisis that the two communist powers had broken with each other, defense planners continued to size force requirements for possible simultaneous conflicts with both.[3] It was it was only some years after the Nixon breakthrough with China, as the Vietnam War was coming to a close, that the United States no longer viewed China as a threat against which to plan and program military forces.[4] The Soviet Union and the Warsaw Pact remained the major threat that concerned defense planners, and did so until the Pact’s dissolution in July 1991 and the Soviet Union’s collapse five months later.

Despite having planned for the possibility of multiple simultaneous conflicts, the United States and its NATO allies never actually went to war with the Warsaw Pact states throughout the entire span of the Cold War. As a result, the United States was never involved in more than a single conflict, whether that was a major war like Vietnam, or the first Gulf War, or lesser operations such as those in Grenada, Lebanon, Panama, or the Balkans.

In the 1990s, the Clinton administration did not jettison the notion that the United States might become engaged in two conflicts, but the Defense Department’s so-called “Bottom-Up Review” (BUR) assumed that those conflicts would be “regional,” similar to the Vietnam conflict. These wars were most likely to take place on the Korean Peninsula and the Middle East, notably against Iran, but they would not involve a conflict with a peer or near-peer competitor. Moreover, and perhaps because the threat was not from a true peer, or even what came to be called a “near-peer,” the BUR postulated the notion of “win-hold-win.” While fighting against one adversary, Washington would only need to commit forces to “hold” the other adversary’s advance until America won the first conflict. Only then would it commit sufficient forces to defeat the second adversary.

However, in the aftermath of the Cold War, the United States had begun to draw down its forces to reap a “peace dividend.” It simply did not have the wherewithal to fight two separate wars simultaneously if neither of its two adversaries was willing to wait until the other conflict had ended and thereby face the prospect of fighting the United States on its own. The wars in Afghanistan and Iraq demonstrated the weakness of the “win-hold-win” approach. Once the United States and its allies went to war against Saddam Hussein in 2003, Washington simply ceased to pay the same degree of attention to what until then had been a successful Afghanistan operation. As a result, both wars dragged on well beyond the length of any previous American conflict since the founding of the Republic. Moreover, America reprised its ignominious departure from Vietnam with a chaotic exit from Afghanistan. While it left an Iraq that was more democratic, it nevertheless had created an opening Iran to exert far more influence in that country than it had for centuries, while also helping to incubate the Islamic State.

Moreover, while bogged down in these “forever wars,” a group of key states dissatisfies with the parameters of the US-led international order were looking for ways to challenge and alter it more to their liking. Yet, for much of the past three decades, Washington remained oblivious to the prospect that China, Russia, Iran, and North Korea, all of which were actual or potential adversaries, might act in concert in pursuit of their efforts to challenge US leadership. Successive administrations certainly responded, at least to some degree, to specific actions on the part of these four states, but certainly not to any degree that would have deterred them from further aggressive activity if they were to act in concert.

China has emerged as a major threat to the United States and its Pacific allies, notably Japan, South Korea, and the Philippines. It has become increasingly aggressive in its claims to control the entre South China Sea. It has ramped up its strategic nuclear arsenal, moving at an unprecedented pace to reach 1000 warheads by the end of the decade. It has continued to expand its conventional military forces, notably the People’s Liberation Army Navy (PLAN). Finally, it has forged ahead in space, cyber, and cutting-edge technologies, including biotechnology, where it threatens to overtake America’s long-standing lead.

Finally, Russia seeks to reconstitute its position as a great power and restore as much of its empire as possible. As a Finnish diplomat who served in Moscow, and is one of that country’s leading experts on Russia, told me, President Vladimir Putin had shifted the National Archives from the Ministry of Culture to the Presidential Office in order to acquaint himself with all Tsarist agreements that led to the expansion of the Russian Empire.

All of these developments continue to pose dangers to American interests on their own, but the most serious threat to American security consists of a combination of these aggressors acting in concert as an “Axis of Upheaval.”[5] That alliance has manifested itself most clearly in the Ukraine war.

As of June 2024, North Korea is a formal Russian ally. Kim Jong Un and Putin signed a comprehensive strategic partnership treaty, which includes a mutual defense clause.[6] Approximately 12,000 troops from North Korea’s special forces deployed to Russia four months later. They have been fighting alongside Russian troops in the Kursk region while 3,000 additional troops have deployed to replace battlefield losses. These forces have helped Russia reconquer some of the territory it had lost to Ukraine.[7] North Korea has sent thousands of construction workers to replace Russian personnel fighting in Ukraine.[8] It has also dispatched 1,000 combat engineers to Kursk to assist Russia’s efforts to demine the area.[9] Since 2023 North Korea has delivered anywhere from $5–10 billion worth of arms to Russia. These shipments include “millions of artillery shells, mortar rounds, and rockets, hundreds of artillery pieces and launchers, short-range ballistic missiles.”[10] In July 2025, sources citing South Korea’s Defense Intelligence Agency estimated that North Korea had sent more than 12 million artillery shells in total, with some Russian units at times coming to rely almost exclusively on North Korean-made artillery.[11] Finally, Russia has been deporting Ukrainian children to North Korea.[12] For its part, Moscow has Russia has provided financial support to Pyongyang’s defense programs. It has transferred advanced electronic warfare and air defense systems, as well as anti-aircraft missiles. Moscow is also aiding North Korean ballistic missile development. Finally, it has provided North Korea with anti-aircraft missiles.

Russia also signed a Comprehensive Strategic Partnership with Iran in January 2025, and in December the two countries signed a program for coordination on political, economic, cultural, defense and security matters.[13] The Russo-Iranian agreement does not include a mutual defense clause but, like North Korea, Iran has provided significant support to the Russian invasion of Ukraine. This has unmanned aerial systems (UAS), artillery shells, and Fateh-110 short-range ballistic missiles. Iran has participated in the construction of a UAS factory in Russia capable of producing thousands of military drones. Russia has supplied Iran with Yak-130 pilot training aircraft, Mi-28 attack helicopters, aid to Iran’s space and missile programs, and domestic surveillance technology. Finally, Chinese-Russian relations have gone from strength to strength, and are a far cry from the days when Beijing was a virtual American ally against Soviet Russia. In February 2022, just days before Russia invaded Ukraine, China and Russia announced a “no-limits” partnership. That partnership has manifested itself over the course of the Russo-Ukrainian war. Initially it appeared that China was providing Russia with sanctioned components and “dual use” technologies employed in the production of missiles, tanks, and aircraft.[14] In particular, just one year into the war with Ukraine, China accounted for 89 percent of Russia’s microchip imports. In addition, approximately 47 percent of the chip-making equipment and 58 percent of spare parts used in Russia were of Chinese origin.[15]

By mid-2024, however, Ukrainian president Volodymyr Zelenskyy was accusing China of supplying Russia with weapons and gunpower, and Chinese citizens were working at a drone production plant in Russia.[16] Indeed, in late 2024 the US State Department confirmed that China was providing Russia with what then Deputy Secretary of State Kurt Campbell described as “component pieces of a very substantial effort on the part of China to help sustain, build and diversify various elements of the Russian war machine.”[17] Most recently Ukraine’s Foreign Intelligence Service asserted that it had recorded evidence of China’s transfer of satellite data to Russia, which was used to launch missile strikes on strategic targets, including objects owned by foreign investors.[18]

Russia has reciprocated. Most notably, Moscow has supplied components and training necessary for airborne and amphibious operations, which would be critical in a Chinese invasion of Taiwan,[19] but also would enable China to seize key islands, reefs and shoals in the South China Sea.

It is true that this “axis” or “entente” is not a formally constituted alliance, as Russia’s unwillingness to provide more concrete assistance to Iran during its 12-day war with Israel in 2025 clearly indicates. The members of this entente are not prepared to see an attack on one as an attack on all.

Nevertheless, the 2026 National Military Strategy, like its predecessors, appears to overlook the implications of cooperation among the Axis states for American security. America is a Pacific power, and China’s military expansion, especially if it were to conquer Taiwan, could threaten Guam, American Samoa, and other American Pacific outposts. Yet China might not act alone. It could receive direct support from its partners in the Axis. Or, if America focuses on defending Taiwan, Russia might choose to invade a NATO country, North Korea might attack the South, and Iran might ramp up its support for its regional proxies, notably the Houthis, who would resume attacking Western shipping. China might also, in conjunction with its partners, look to create diversions in other theaters, not only in Europe and the Middle East but also in the Arctic, in sub-Saharan Africa, and in Latin America.

In short, the simultaneity challenge would not simply be to involve the United States in multiple conflicts but to spread US attention, resources and capabilities thin across different and disparate theaters of action.

Two or more simultaneous conflicts clearly demand a significant increase not only in defense spending but even more importantly in defense production. There is a clear need for a much larger fleet and air force that can operate at strength in multiple theaters. There also is a requirement need for an expanded army force posture to deter further Russian expansionism, especially if America is engaged in a conflict elsewhere in the world. Expanding the US Army’s long range strike capability is needed both for operations in Europe and as a key supplement to for maritime and air operations in East Asia. An increase in space and cyber capabilities must also accompany other force increases.  

President Donald Trump has called for a $1.5 trillion defense budget for fiscal year 2027, an increase of more than 50 percent over the $901 billion fiscal year 2026 request. Yet there is a risk that most of those additional funds might be directed toward the president’s Golden Dome project, which could amount to as much as $6 trillion.[20] He is also seeking a fleet of at least 20 new battleships that could cost as much as $15 billion each.[21] It is imperative that the budget increase be employed most efficiently to ensure that the United States has sufficient capabilities to address the simultaneity challenge.

To that end, the defense industrial base must expand to include as many new entrants as possible. In doing so it would enable the Defense/War Department to best exploit in timely fashion cutting-edge technologies for battlefield use, and thereby prevent America from falling behind China, which continues to surge its military capacity. In addition, an expanded industrial base would be best positioned to accelerate weapons and munitions production. Trump is pushing industry to be more responsive; whether he will succeed, and especially whether industry can get past the so-called “valley of death,” where many promising programs terminate, remains an open question.

Increasing the defense budget is a necessary, but insufficient condition for meeting the threat of a multi-front conflict. America needs her allies, to bolster her own capabilities to deter adversaries in Europe, Asia and the Middle East. To be credible, however, both European and Asian allies must maintain, if not accelerate, the pace of their current increases in their own defense budgets. In conclusion, if defense spending and programs can be reoriented to address the huge demand that the need for simultaneously confronting all members of the axis of resistance implies, and if America ensures that its allies remain committed to supporting the common defense, it will be far less likely that the United States will find itself actually fighting those increasingly interlocking anti-American states in the years to come.