There is, of course, no single answer, but a number of things have changed since the Intermediate-Range Nuclear Forces (INF) treaties were created about 30 years ago, that might be helpful in understanding why leaders on both sides have made statements questioning value of the bilateral agreement to their respective countries.
But concerns not directly related to INF must also be considered as well. In the view of NATO, the Annexation of Crimea by the Russian Federation in 2014, and Putin boasts of new Russian nuclear weapons in 2018 have set the stage for deterioration in international relations. But specific issues related to the INF treaties are probably most relevant:
Sunsetting of On-site Inspection
When the INF treaties were signed, they included a set of verification measures that permitted the parties to gain confidence that the other terms of the treaty were being followed. One of these verification measures, on-site inspections, came to an end in 2001. With the inspection part of the agreement no longer in effect, it has become difficult for either side to verify compliance of the other.
Proliferation of Technologies
The INF agreement was bi-lateral, it only restricted two countries. Since then, other countries have developed both nuclear weapons, and missiles with a ranges sufficient to be threatening to both sides of the original agreement. Today China, France, India, Israel, North Korea, Pakistan and the UK are thought to have such capabilities.
Only Ground Launched Missiles Covered
The INF agreements were limited to ground launched missiles, and did not cover either air- or sea- launched weapons of similar range. These systems further complicate the matter of verification of limits to ground launched missiles, and both side's arguments that the other is not in compliance involve systems originally designed for shipboard use.
Confusion between Offensive and Defensive Missiles
In the question reference is made a missile defense system in Poland and Romania. The NATO position on this is that these are strictly defensive missiles, including anti-ballistic missiles (ABMs), that are not covered under the INF treaty. The missiles in these locations are US built SM-3 interceptors, but the claims from Vladimir Putin seem to be that the ground facilities could be used to fire some hypothetical ground launched cruise missile.
Article VII of the INF is explicit that interceptors like the SM-3 are not covered:
- If a GLBM is of a type developed and tested solely to intercept and counter objects not located on the surface of the earth, it shall not be considered to be a missile to which the limitations of this Treaty apply.
Putin's accusation may have been the breaking point for the INF treaty. Defensive missiles had previously been limited under the 1972 ABM treaty, which the US withdrew from in 2002. Russia has produced and deployed numerous ABM systems, including the A-35, A-135, and A-235, and indications are that the S-500 ABM is targeting deployment in 2020. Attempts to limit NATO deployments of ABMs under INF interpretation seem inappropriate, but could drive the INF treaty to end.
Timeline of events regarding withdrawal from INF
In October 2007, Luke Harding reported that Vladimir Putin had threatened to withdraw from a treaty generally assumed to be INF. The article quotes Putin as saying:
We need other international participants to assume the same obligations which have been assumed by the Russian Federation and the US.
It goes on to report Putin said:
If we are unable to attain such a goal... it will be difficult for us to keep within the framework of the treaty in a situation where other countries do develop such weapons systems, and among those are countries in our near vicinity,'
Beginning in 2013 the US raised concerns over an apparent violation of the INF agreement, specifically in In a July 2014 unclassified report, the U.S. State department said:
The United States has determined that the Russian Federation is in violation of its obligations under the INF Treaty not to possess, produce, or flight-test a ground-launched cruise missile (GLCM) with a range capability of 500 km to 5,500 km, or to possess or produce launchers of such missiles.
In 2013, the United States raised these concerns with the Russian Federation on repeated occasions in an effort to resolve U.S. concerns. The United States will continue to pursue resolution of U.S. concerns with Russia
In an June 2015 unclassified report, the U.S. State department reported counter-claims by Russia:
In bilateral meetings with U.S. officials relating to the INF Treaty, Russia claimed that the Aegis Ashore Missile Defense System launcher was capable of launching INF-range offensive ground-launched ballistic or cruise missiles and therefore, was inconsistent with the Treaty. As explained in detail to Russia, the U.S. Aegis Ashore Missile Defense System is fully consistent with U.S. obligations under the INF Treaty: it was designed and tested for missile defense purposes only and does not have an offensive capability. As such, the Aegis Ashore Missile Defense System is not a prohibited launcher. Russia also again raised concerns relating to armed unmanned aerial vehicles (UAVs) and ballistic target missiles, both of which we previously had addressed in the Special Verification Commission.
In February 2017, the New York Times reported Russian had secretly deployed missile in question and indicating it carried the NATO designation SSC-8 (Russian designation 9M729). It went on to say:
The Obama administration had sought to persuade the Russians to correct the violation while the missile was still in the test phase. Instead the Russians have moved ahead with the system, deploying a fully operational unit.