In February 2018, when Russia announced that it completed reductions of its strategic forces under the New START, it also issued a statement that asserted that the United States reached the limit in part by

converting a certain number of Trident II SLBM launchers and В-52Н heavy bombers, in the way that the Russian Federation cannot confirm that these strategic arms have been rendered incapable of employing SLBMs or nuclear armaments for heavy bombers.

There was another charge as well - some reductions were done by

arbitrary renaming silo training launches into "training silos," a category not specified by the Treaty.

A later statement issued by the Foreign Ministry provided more details. Russia believes that 56 Trident launchers and 41 B-53H bombers were converted in a way that does not render them incapable. With "training silos" we are talking about four silos (curiously, the number is mentioned only in the Russian version of the statement).

Although at the time the tone of the statements was rather reserved - Russia noted the fact and said that the issue is "of fundamental significance" - the stance appears to have hardened since then. Speaking at a session of the Council on Foreign and Defense Policy, Vladimir Ermakov, director of the Department for Nonproliferation and Arms Control of the Ministry of Foreign Affairs, said that the New START extension can only be discussed when the United States "fully return to complying with the spirit and the letter of the treaty" (h/t DS).

It appears that Russia has made a decision to elevate the issue to the level of accusing the United States of non-compliance with New START.

Since things get that serious, it makes sense to take a look what this is all about. When I tried to look into the issue in February my conclusion was that more information would be necessary to understand it. So, I asked around and I believe that at this point I have a reasonably good picture of what is going on.

Trident II and B-52H

The treaty does allow parties to convert launchers or heavy bombers "by rendering [them] incapable of employing ICBMs, SLBMs, or nuclear armaments" (see paragraph I.3 in Part Three on p. 90 of the Protocol). Once this is done, "such a converted strategic offensive arm shall cease to be subject to the aggregate numbers."

It is indeed the case that the United States converted some of its Trident II launchers this way - the 56 launchers in question are four launchers on each of the 14 submarines that carry the missile. As I understand, the conversion was done by removing gas generators of the ejecting mechanism from the tube and bolting the tube covers shut.

The problem that Russia has with that procedure is that it is reversible, as it indeed appears to be. The argument made by the United States is that New START does not explicitly require the conversion to be irreversible, and that as long as the treaty is in force Russia can always use its inspection provisions to check that the launch tubes remain "rendered incapable" of launching SLBMs.

The treaty does require, however, that the procedure is done in a manner "that the other Party can confirm the results of the conversion." If the procedures "are ambiguous or do not achieve the goals" of the conversion, the converting party shall conduct a demonstration, presumably to convince its counterpart that there the goals of the conversion are achieved. But the treaty does not, in fact, require the demonstration to be convincing, so it is entirely possible that the other party will still have issues with the way the conversion is done. Which appears to be exactly what happened.

My take is that Russia probably has a point here. It does have the right to "confirm the results of the conversion." The treaty does not say it explicitly, but it is clear that the idea of this requirement is that Russia has to agree that the procedure does what it is supposed to do. As I understand, the United States does not dispute the fact that the conversion of Trident tubes is reversible. Yes, replacing the gas generator and unbolting the cover may not be a trivial procedure, but since the tube can still be used to deploy an SLBM, it would be more appropriate to consider it a "non-deployed launcher," which means it cannot be excluded from the New START aggregate numbers. If the United States wants to exclude these tubes from the New START count, it should pour concrete in them or do something similar.

I don't have details of the B-52H conversion, but I would guess that the conversion is done in a reversible manner as well. But bombers has always been tricky, since their conversion is never truly irreversible. As I understand, it is largely an issue of having a socket that allows the arming mechanism of a nuclear weapon to be connected to the equipment inside of the aircraft. There is the equipment itself, of course, but its absence is more difficult to verify. But with bombers at least there is an understanding of the risks and there are arguably other ways to ascertain that a bomber has been converted to non-nuclear missions. That's not the case with submarines and SLBMs.

As I understand, at some point last year Russia and the United States considered an option of issuing a joint "agreed to disagree" statement that would outline their differences on the issue. But something didn't work out.

UPDATE 04/18/18: In fact, the Protocol describes the conversion procedure (h/t AS). It's on pp. 95-96, reproduced below:

The important words here are "carried out using any of the procedures." So, pouring concrete as in (a) is an option, but removing a gas generator is an option too. The latter, however, may be accompanied by a removal of some "launch-related systems," but maybe not. So, maybe Russia's point is not as strong as I thought it is. But there is still a point there.

Training silos

Unlike the Trident claim, this one seem less serious. At the center of the issue are four "training silos" at the three operational ICBM bases (there are two at the F.E. Warren AFB).

The reason these are not reported in the treaty is that the United States maintains that they should not be. New START requires counting "silo training launchers," which are defined as "full-scale silo launcher of ICBMs specified for training purposes" (see p. 12 of the Protocol. It's полномасштабный in Russian).

In U.S. view "training silos" are different from "training launchers" in one very important aspect - "silos" are not "full-scale" launchers in that even though they are replicas of the real thing and are indeed used for training, they cannot possibly launch a missile.

I am largely with the United States on this one - "full-scale" does imply the capability to launch, so if a silo cannot do that, it shouldn't be counted. It is true, though, that in the "old" START these silos were reported as "silo training launchers," so the United States should probably demonstrate why it no longer considers these silos as launchers. So, Russia may have a point again.

Verifying this should be fairly easy. It wouldn't even require using the treaty inspection quota - F.E. Warren AFB at some point offered a public tour of its training silo, so I'm sure it can be easily arranged again. But at some point it should be done.