Your opinion is wrong; this is not anything remotely like sufficient grounds to move forward with new cold war escalations. Firstly, they say “of a type developed in Russia” and not “that was developed in Russia” for a reason; all they know is that the Soviets developed novichok in the past, not that the Russians developed the novichok used in the Skripal attack. We know from a new statement by the Porton Down laboratory’s executive chief that there is no evidence within the compound that it came from Russia, which the UK government lied about and is trying to cover up.
Any former Soviet state had access to the science which developed this nerve agent, including western allies like Ukraine. Additionally, comments from the head of the Porton Down lab indicate that the UK does in fact have novichok in its stockpile, because he said it couldn’t have come from Porton Down not because they didn’t have any, but because they have great security. Additionally, the United States was involved in dismantling the facility where these compounds were made and has been actively suppressing information about them. Additionally, an Iranian scientific paper found that it wouldn’t be difficult for any government to produce the compound at bench scale. Additionally, the recipe for the compound is publicly available on Amazon for $28.45.