While I find the Russian invasion of Ukraine appalling, as a counterpoint to all the "Trump is destroying the US' reputation" mono-point that I've read so far (although I agree with that, too): John Maersheimer [1] gave a great explanation and prediction (~10 years prior) of why the whole thing happened. The US saw Russian weakness, decided to expand NATO to Ukraine, and the Russians said "no way will we let NATO be…
Actual history shows NATO bent over backwards to appease Russia (hint how many non local troops did nato have near russian borders before 2022? Almost none)and that Ukraine was not about to join NATO in 2022 or 2014 and that everyone including Putin knew this. Hell after the revolution of dignity but before the Russian invasion of Ukraine/local coups(Crimea in the south and parts of eastern Ukraine) Ukraine wasn't even seeking to join NATO, it was seeking to join the EU (which was also at best a difficult goal tha5 would take a long time).