Justice should not be arbitrary.
Past US activity in the Middle East is widely perceived as unjust, in the US and internationally. And even so, the West is still generally perceived as having more moral authority than e.g. Russia, China, etc., and although this authority is flawed, the reasons for the perception are not strictly "arbitrary", obviously.
How is...the other [country] not even permitted to exert influence over its own neighbors?
There would be worldwide outrage if the US invaded Central America in order to narrow its defensible border by expanding south. What kind of "influence" are you proposing is acceptable? There are many channels of influence, Russia has chosen the bluntest possible, and no it is not permitted. Russia has legitimate geopolitical goals in Ukraine, fine; does desire justify its own satisfaction at any cost? No; they can pursue by other means, or alter their goals. Would there be no objection if NATO, by virtue of its military superiority, simply invaded Russia? Absurd. Do you propose that the concept of sovereignty itself is a complete farce and should be ignored by everybody? You are sad that Australia has a lopsided economic relationship with other western countries by virtue of it being a weaker country, so you satisfy yourself with gloating over the domination of another weaker nation. There is a title for people who enjoy such things.
Is Russia supposed to become part of the EU?
"Uh oh, the Germans are sexually degenerate, better start shelling Kyiv." What is this dichotomy? The diminution of Russia's stature hardly justifies war, and the preservation of their moral sanctity is hardly related. If anything they would have a better chance of staying morally intact if they relinquished all their wealth and became a hermit nation. Blessed are the poor.
You are disingenuous or willfully blind, probably both.