This stance by Russia is absolutely logic. But it is only a stance and not a de-facto action, as Putin combines this threat of pointing Russian missiles on Ukrainian soil to possible Anti-Missile shields in Ukraine by USA and NATO.
This would decrease a strategic balance between the nuclear powers USA and Russia and raise the first strike capability of USA against Russia.
Anti-Missile shield in countries like Poland and Ukraine is not explainable with Iranian Missiles. Interception of Iranian Missiles follows through e.g. Azerbaijan, Georgia, Greece and Turkey.
And here is Russia absolutely right with its stance because USA tries to legitimate these missile deployments with a threat of Iran, allthough the motive lies clearly at Russia.
It does also not matter, what the motive of USA really is, even if the missile shield is not directed at Russia, Russia sees its interest negative effected by this missile shield potentially being able to intercept also Russian Missiles.
From such a national security perspective it is legitimate that these missile installations are one of the first assets, Russia would destroy in a conflict. Pointing them solely is no act of aggression.