We should collectively care. In 1991 Ukraine had the world third nuclear arsenal stationed on its territory. Giving in to international pressure, Ukraine agreed to renounce its nuclear power status, and to join the nuclear non-proliferation treaty, in exchange for assurances regarding the respect for its sovereignty, security and territorial integrity.
Co-signatories of the agreement (Budapest Memorandum) were the United States, Russia and Great Britain, with endorsement from France and China.
Of the three signatories, only the United Kingdom has supported Ukraine with consistency and admirable courage, through several conservative premierships and a labor one. France also has bravely supported Ukraine, despite not being a signatory of the Memorandum.
The Biden administration, on the other hand (and it's my opinion), has been too hesitant and duplicitous in supporting Ukraine, despite the USA clearly accepted the role of being the main guarantor of Ukraine sovereignty against any Russian pretense or aggression.
Please note that the Budapest Memorandum provided Ukraine with assurances with regards, among the others, to:
1. Respect the signatory's independence and sovereignty in the existing borders.
2. Refrain from the threat or use of force against the territorial integrity or political independence of the signatories.
3. Refrain from economic coercion designed to subordinate to their own interest the exercise by Ukraine of the rights inherent in its sovereignty and thus to secure advantages of any kind.
Nowhere was agreed that Ukraine shall never join NATO or be part of the EU. In fact, being independent and sovereign gives Ukraine the right to choose its place on the international stage. Russia had no right to object nor to start its criminal war against a sovereign nation.