There are already NATO nations on Russia's border and another, Finland, just joined. Ukraine is a sovereign nation and shouldn't be dictated to by Russia. It's a matter of coveting Ukraine's resources. The government overthrown in 2014 was Putin's puppet. The Ukrainians voted for Zelensky. He wasn't installed.Ukraine flirting with NATO would be like Mexico or Canada flirting with joining the Warsaw Pact in the 1980s. Do you think the US would have allowed it? We didn't even allow Cuba to get nukes in the 1960s. Russia doesn't want a country that has historically been under their control to go an join the west and put nukes right up on their border. Moreover, Ukraine's government was overthrown in 2014 and had a western puppet government installed in its place. The problems with Ukraine and Russia have been brewing for a while now.