German and American arms control experts accuse the US government of missing a chance to rescue the INF treaty banning land-based nuclear weapons.

The Russians had offered the US on Tuesday in Geneva to inspect their cruise missile SSC-8 on site. For years, the Americans claim that the cruise missile violates Moscow's INF treaty. The Kremlin denies that.

According to Jon Wolfsthal, once disarmament adviser to Barack Obama, the Russian offer is a "big step forward". Even Obama's former top diplomat Alexandra Bell sees it as a possibility, reports the Guardian; Washington should take up the proposal and negotiate it. Bell and Wolfsthal are not suspected of being friendly to Russia. But the US delegation refused, the Russian initiative could not help clarify Moscow's contracting.

Experts consider on-site inspection sufficient

The 1987 INF Treaty bans Russian and American land-based medium range weapons with a range of 500 to 5500 kilometers. According to US data, the SSC-8 was tested over 2600 kilometers, whereas Russian data only tested 480 kilometers.

Robert Schmucker, former UN weapons inspector, and Wolfgang Richter, former Bundeswehr verification expert, consider an on-site inspection to be sufficient to clarify this big difference. All you have to do is know the length and diameter of the SSC-8.

However, on-the-spot inspections were not enough to detect small overshoots of the 500 kilometer limit. This would require a data exchange and a flight demonstration, these would provide information about the engine thrust or the mass ratio between warheads and tank filling. So far, the Russians do not offer such information.

Flight test under Russian control is not verifiable

The US delegation in Geneva justified its rejection with the fact that the observation of a dormant cruise missile does not tell how far it can fly. And a flight test, which is carried out under the control of Russian military, is not verifiable.

It is unclear why the Americans did not make a counterproposal. US President Donald Trump has announced that he will suspend the INF treaty on February 2, unless the Russians have solved the SSC-8 problem to American satisfaction by then. NATO supports the ultimatum of Washington.