Washington violated the Intermediate-Range Nuclear Forces Treaty by deploying the Mark 41 Vertical Launching Systems in Poland in Romania.
The Intermediate-Range Nuclear Forces Treaty is the abbreviated name of the Treaty between the USA and the USSR on the elimination of their intermediate-range and shorter-range missiles signed in 1987 also known as the INF Treaty. The INF Treaty implies the elimination of all nuclear and conventional missiles, as well as their launchers, with ranges of 500–1,000 kilometers (310–620 mi) (short-range) and 1,000–5,500 km (620–3,420 mi) (intermediate-range). The treaty did not cover sea-launched missiles.
The Mark 41 Vertical Launching System (Mk 41 VLS) is a shipborne missile canister launching system which provides a rapid-fire launch capability. The very fact that the US uses a shipborne missile launcher on the surface automatically violates the INF Treaty and may trigger unpredictable consequences for the world stability.
The Mk 41 is capable of firing short-range and intermediate-range missiles. However, it can also carry long-range missiles such as Tomahawk which operational range is up to 2500 km (1553 mi).