In the long run?

British Prime Minister Boris Johnson may be right, that if Putin does occupy Ukraine by force, it will ultimately be to his and Russia's detriment in the long term. But in the short term lives will be lost and in the medium term, at least until Ukraine is able to return to sovereign self-rule, Ukrainians will pay a heavy price, from loss of freedom to economic stagnation under Russian or "Russian approved" governance. That should net be seen as acceptable. If the West is serious about defending democracy, perhaps it should admit Ukraine to NATO immediately and begin moving troops and military assets into the country to defend it in the face of Russia's current and possible future aggression.