The scenario of Ukraine invading neighboring Poland, Slovakia, Hungary, and/or Romania is a political fantasy, especially since it would trigger Article 5’s mutual defense clause.
The Kissinger interview is a very interesting (long) read. I also found his NATO membership argument odd but I think you are misrepresenting what he said. As far as I remember, he nowhere claims that Ukraine will outright invade its NATO neighbors. He is pointing out that we will have a highly armed, unhappy Ukraine with an erratic leadership possibly running amok. This would be a threat to everyone around, including and foremost to Russia and Belarus. That's an analysis that the Russian elites can probably fully aggree with. However, he then draws a conclusion that is the exact opposite of what his Russian counterparts would think of in terms of how to prevent this from happening. He argues that NATO membership will in fact stabilize or rather forcefully discipline Ukraine. He explicitely argues that Ukraine NATO membership therefore would be in Russia's interest. It actually shows that he sees NATO as a power instrument that can forcefully bend member states to the will of the US. It also suggests that NATO (the US) can find an agreement with Russia and that NATO (the US) is the only one who could, in fact, enforce and guarantee this agreement.
I don't think this is a convincing argument given how the US and NATO have helped escalating the conflict at every stage -- but for Kissinger, this was not the doing of "the US" but of the neocon clique within that he clearly despises. Nevertheless, one would think that, however unhappy, post-war Ukraine would totally depend on Western financing, which should be a pretty good disciplining tool by itself. But the "Kissinger plan" is still an interesting attempt to sketch out a solution that, first of all, realizes US interests but packaged up so that it is acceptable (or without alternative) also to the Russian side: you give us Ukraine, in return you can keep Crimea and we guarantee peace.
Perhaps the more interesting is what Kissinger didn't say: He never uses the standard formulas about Russia's "unprovoked" "war of agression". On the contrary, he almost literally repeats the old William Burns argument about Ukraine NATO membership crossing the "brightest of red lines" for Russian elites. He refrains from any Putin-bashing, and is, between the lines, completely exhausted by the Biden team's incompetence. In fact, he forcefully singles out the very same William Burns as a potential leader for settling the conflict between the US and China. I think that in itself is a quite strong message also with respect to team Biden and the Ukraine war.
The Kissinger interview is a very interesting (long) read. I also found his NATO membership argument odd but I think you are misrepresenting what he said. As far as I remember, he nowhere claims that Ukraine will outright invade its NATO neighbors. He is pointing out that we will have a highly armed, unhappy Ukraine with an erratic leadership possibly running amok. This would be a threat to everyone around, including and foremost to Russia and Belarus. That's an analysis that the Russian elites can probably fully aggree with. However, he then draws a conclusion that is the exact opposite of what his Russian counterparts would think of in terms of how to prevent this from happening. He argues that NATO membership will in fact stabilize or rather forcefully discipline Ukraine. He explicitely argues that Ukraine NATO membership therefore would be in Russia's interest. It actually shows that he sees NATO as a power instrument that can forcefully bend member states to the will of the US. It also suggests that NATO (the US) can find an agreement with Russia and that NATO (the US) is the only one who could, in fact, enforce and guarantee this agreement.
I don't think this is a convincing argument given how the US and NATO have helped escalating the conflict at every stage -- but for Kissinger, this was not the doing of "the US" but of the neocon clique within that he clearly despises. Nevertheless, one would think that, however unhappy, post-war Ukraine would totally depend on Western financing, which should be a pretty good disciplining tool by itself. But the "Kissinger plan" is still an interesting attempt to sketch out a solution that, first of all, realizes US interests but packaged up so that it is acceptable (or without alternative) also to the Russian side: you give us Ukraine, in return you can keep Crimea and we guarantee peace.
Perhaps the more interesting is what Kissinger didn't say: He never uses the standard formulas about Russia's "unprovoked" "war of agression". On the contrary, he almost literally repeats the old William Burns argument about Ukraine NATO membership crossing the "brightest of red lines" for Russian elites. He refrains from any Putin-bashing, and is, between the lines, completely exhausted by the Biden team's incompetence. In fact, he forcefully singles out the very same William Burns as a potential leader for settling the conflict between the US and China. I think that in itself is a quite strong message also with respect to team Biden and the Ukraine war.