[wheelerof4te]

"Russians now sell a lot of oil to India for rupees (and note that there does not seem to be any initiative to bomb India for engaging in this trade), but then are basically forced to use those same rupees to buy stuff from India again".

That is how the world economy used to work, before the petrodollar.

Now, Saudis or Qatar or pick your favorite Middle eastern monarch sell oil to US and everyone else in exchange for $USD. Since oil is used in nearly every other product line, either for transport or actual product, now world trade depends on how much $USD you have to buy said oil.

Euro is irrelevant outside of Europe.