While the United States has no shortage of opponents on the military or diplomatic stage, few present such a looming threat as the nations of China and Russia. America‘s historical Cold War opponent may not have the same military might behind its bluster that it had during its Soviet hay-day, but Russia has demonstrated a powerful capacity to do a great deal with very little in recent decades — managing to keep their names in discussions about the world’s most advanced and powerful weapons systems despite a woefully stagnant economy and shrinking defense budgets. China, on the other hand, has seen nothing but expansion and modernization throughout its military forces in recent years. As the world’s second most powerful economy, China has demonstrated a newfound interest in global expansion, which places both its goals, and its military, at odds with the American presence in the Pacific.

Each of these nations represent challenges to American foreign policy and the potential for a military opponent. In Europe, the United States is currently preparing for its largest war game deployments since the Cold War, with 20,000 troops headed to the continent in the coming months to train for a rapid response to a Russian invasion. In the Pacific, China’s rapid — and considered by most to be illegal — expansion throughout the South China Sea has left the U.S. scrambling to find ways to counter China’s massive stockpiles of ballistic and cruise missiles, some of which are hypersonic, and as such, considered indefensible.

Individually, these nations each possess the military capability to be a reason for concern among American defense officials, but if these two seemingly disparate nations were to form a military alliance, that combination would not only represent a far greater threat, but a far more complex diplomatic environment. The combined military power represented by a Sino-Russian alliance would award them a great deal of leverage in international relations and discussion, provided, of course, that the ruling regimes of both nations could see eye to eye on their overarching goals.

That’s an important element of how military power informs foreign policy that all too often goes ignored: physical conflict doesn’t need to take place in order for military power to grant diplomatic leverage. In fact, it’s not force, but rather the threat of force that grants a nation unspoken power in foreign negotiations. In that regard, Russia and China wouldn’t need to literally be able to sustain open war with America and its allies for its combined military power to pay dividends. The threat of what such a conflict would do to our world would force all nations involved to weigh their positions more carefully than they would otherwise have to.

Earlier this month, Vladimir Putin announced that Russia has formally entered into an agreement with China to help them develop an early warning missile defense system. This military partnership would seem to be directly aimed at America‘s own missile programs, as Russia, China, and the United States are currently embroiled in a three-way race to begin fielding the most capable hypersonic missile systems. China’s hypersonic anti-ship missiles, in particular, pose a serious threat to American carriers, and as such, are the focus of America‘s own offensive strategies.

While many experts and academics in the foreign policy field dismiss the idea of a Sino-Russian alliance over differences in culture, approach, and goals, Putin emphasized the growth of ties between the two nations, even using the word alliance specifically, in his remarks earlier this month. In this instance and others, it was competition with the United States that seemed to bind the two nation’s interests.

“China provides the liquidity and Russia provides the natural resources and the necessary know-how in key fields such as diplomacy, defense, space, etc.,” Velina Tchakarova, head of the Austrian Institute for European and Security Policy, said, adding that “a new connectivity is being explored and expanded such as in the Arctic, Central Asia and beyond to balance the U.S.-dominated global supply chains.”

It’s worth noting, however, that Tchakarova’s overall position is that the ties between China and Russia will only last as long as their interests are precisely aligned.