Ukraine was part of Russia for 400 years. Venezuela and Cuba, not so much.
Russia doesn’t want to have Ukraine. It’s a black hole & failing state. If the Ukrainians attack in Donbass, Russia will reunite with the parts of Ukraine that were Russian before Lenin drew the internal Soviet boundary and put them into today’s Ukraine (as Khrushchev did with Crimea). But hopefully that won’t happen.
“Ukraine that were Russian before Lenin drew the internal Soviet boundary and put them into today’s Ukraine “
To be clear neither the Donbass nor Crimea were Russian culturally until 1944 when Stalin deported the local Tartars and Cossacks and replaced them with Russian settlers.