Obviously, Putin and the older generation of Russian officials still feel threatened by NATO’s acceptance of 14 new members between 1999 and 2020 - adding Albania, Bulgaria, Croatia, Czechia, Estonia, Hungary, Latvia, Lithuania, Montenegro, North Macedonia, Poland, Romania, Slovakia, and Slovenia.
https://en.wikipedia.org/wiki/Member_states_of_NATO
In countering NATO’s expansion, Putin successfully tested NATO and Western governments by adventures in Georgia and Crimea. If he succeeds in this offensive as he did in Crimea and a small area of Georgia, one can simply look at the map to know which borders Putin will be tempted to cross next. Without advanced and seriously lethal weaponry available at their ready disposal, each former Soviet Republic will remain a sitting duck if it is not a member of NATO.
https://www.washingtonpost.com/archive/politics/2004/03/30/7…
After seeing how callously Putin sends his troops into neighboring lands, people who live in the following countries have reason to fear that Putin may come for them next: Armenia, Azerbaijan, Belarus, Georgia, Kazakhstan, Kyrgyzstan, Moldova, Tajikistan, Turkmenistan, and Uzbekistan.
After witnessing the Russian Army pour into Ukraine from every direction, one starts to understand how military tacticians and arms experts came to believe that the neutron bomb could serve as a deterrent to precisely the type of assault Russia has perpetrated on its peaceful, prosperous, civilized neighbor.
[D]uring the 1970s, the neutron bomb was considered by some American military planners to have a convenient deterrent effect: discouraging an armoured ground invasion of western Europe by arousing the fear of neutron bomb counterattack. At least in theory, a defending NATO country might sanction the use of the bomb to annihilate Warsaw Pact tank crews without destroying its own cities or irradiating its own population.
https://www.britannica.com/technology/neutron-bomb
It now is clear that Ukraine will need many more troops, more advanced weaponry, and lots more ammunition in order to repel Russia’s tanks and troops. If it were better-armed, Ukraine might be able to teach Russia’s arrogant and belligerent nuclear-armed dictator that there are lines he should not cross.
The independence of non-NATO former Soviet Republics will be a lost cause if Putin is successful in taking over Ukraine’s government. In light of the fact that Russia has China supporting its territorial expansion, even independent, formerly Soviet NATO-member states need to be seriously beefing up their forces and advanced weaponry to protect their own people.