too bad that Cuba is right on its own border :)
For all intents and purposes, Ukraine's border with Russia is way further away (like magnitude) from EU/NATO than US<>Russia (who are neighbors) or US<>Cuba (who are also neighbors).
What argument did I even make? Are you saying it's absurd that Russia's border to Ukraine is further away to the closest EU/NATO member than Cuba is to the US? Because if so, I think you need to open up a world map.
1. Russia aims to either capture Ukraine outright or exert influence over it, which puts eastern EU states at grave risk. Note that Belarus, a Russian vassal, already borders the EU and was used by the Russians to launch the Ukraine invasion.
2. Russia already borders — and menaces - the EU in the Baltics.