Oreshnik and the End of Arms Control in Europe.

Why Russia's new missile is the second final nail in the coffin for arms control with Russia.

On the night of November 20–21, Russia launched a missile strike on the Ukrainian city of Dnipro, reportedly featuring a new medium- to intermediate-range ballistic missile called “Oreshnik.”

What we know

At this point, a lot of what can be reasonably known about the missile and the attack is likely understood. The Oreshnik is very likely derived from the Russian RS-26 Rubezh (NATO designation: SS-X-31), which itself traces its origins to the Soviet-designed and built RSD-10 Pioneer (SS-20 Saber).

Development of the RS-26 began in 2008 but was mothballed in 2018 before the missile achieved full operational capability. Like the RS-26, the Oreshnik features a MIRVed payload, meaning it can deliver several independently targetable warheads.

The missile likely shares a similar range with the RS-26. Although Putin described it as a “medium-range ballistic missile,” it is plausible that the Oreshnik falls into the intermediate-range category, with a range exceeding 3,000 kilometers.

The attack targeted Dnipro, likely chosen for its symbolic significance and military-industrial importance. The city has historically been associated with the development and production of long-range missiles during Soviet times, and Dnipro remains home to key missile manufacturing facilities that support Ukraine's ongoing long-range strike programs. However, the strike appears to have caused minimal to no damage to critical targets.

The biggest uncertainty regarding the strike arguably remains whether Russia used up to six Oreshnik missiles, each carrying six warheads, or a single missile armed with six warheads, with the remaining projectiles seen constituting missile debris.

Beyond the technical details of the missile itself, this incident carries broader implications, particularly for the past and future of arms control as well as missile defense. Below I put together some thoughts on arms control, next week’s post will focus on implications for European missile defense.

Oreshnik and the INF Treaty

The Oreshnik serves as further evidence that the Intermediate-Range Nuclear Forces (INF) Treaty was effectively dead long before the United States withdrew under Trump in 2019—and rightly so.

For those who don’t know, the INF Treaty was signed in 1987 between the United States and the Soviet Union. The treaty eliminated all ground-launched ballistic and cruise missiles with ranges between 500 and 5,500 kilometers, along with their launchers, and prohibited their deployment until the treaty collapsed.

Why is the Oreshnik relevant to a dead treaty? As outlined above, the Oreshnik is very likely almost entirely derived from the RS-26, a conclusion also reached by U.S. intelligence.

On a side note, even before the confirmation from U.S. officials, the conclusion that the Oreshnik is not a “new” missile was entirely logical. Russia’s defense industry lacks the capacity for significant innovation, and its missile sector is already operating at maximum capacity. The industry simply does not have the resources to design, develop, test, and produce an entirely new missile. Unless Russia somehow discovered additional capacity and ingenuity—a highly unlikely scenario—the Oreshnik must necessarily be based on an existing missile system.

Given that the Oreshnik and the RS-26 are, to a large extent, the same missile, they likely share many features, including payload capacity, range, and function. If the Oreshnik is classified as a medium- to intermediate-range missile, it is highly probable that the RS-26 also primarily falls within this category, rather than being a strategic intercontinental ballistic missile (ICBM) as claimed by Russia. In other words, the RS-26 very likely fell within the range restrictions imposed by the INF Treaty and, therefore, should never have been developed by Russia.

To be fair to Russia, the INF Treaty did not prohibit the development of INF range missiles (though doing so clearly violated the treaty’s spirit), and it provided opportunities for exploitation.

According to the INF Treaty, the “range capability” of a ground-launched ballistic missile is defined as “the maximum range to which it has been tested” (Article 7(4)). Russia tested the RS-26 as an ICBM at a range of 5,800 kilometers, which allowed Moscow to technically avoid a material breach of the INF. However, already at the time, U.S. officials expressed dissatisfaction with the RS-26, accusing Russia of testing it as an ICBM rather than within lower ranges to circumvent the treaty’s limitations.

Events in recent days have validated these concerns. Had the RS-26 entered service instead of being mothballed, it would very likely have provided Russia with a ground-launched medium- to intermediate-range missile capability, in clear contradiction of its obligations under the INF Treaty.

The future of arms control

It’s worth reiterating that the INF Treaty was suboptimally phrased in this respect, creating a loophole that Russia exploited to bypass the treaty without committing a material breach—though Russia certainly did egregiously violate the treaty with other systems, most notably the 9M729 Novator ground-launched cruise missile (I’ll write a separate post about this one).

The broader issue is that arms control treaties like the INF often struggle to effectively translate complex technical realities into political agreements. (That said, the INF was arguably superior to many other treaties in this regard, given its extensive verification regime.) For such treaties to function properly, both sides must trust that the other will not exploit potential loopholes or undermine the treaty’s spirit, even in the absence of a clear material breach.

In this context, the Oreshnik, with its apparent ties to the RS-26, serves as further evidence that, from at least the mid-2000s, Russia ceased to view the INF Treaty as a genuine arms control tool. Instead, it treated the treaty as a means to create asymmetric advantages over NATO by developing restricted missile capabilities while ensuring NATO remained constrained.

Given this history, why should NATO consider returning to arms control agreements with Russia, even if the opportunity arises? I always say, never say never. However, restoring and rebuilding the necessary trust will likely take decades—much like it did during the Cold War to establish cooperative security arrangements—and will almost certainly require a change in Russian leadership.