Here, let's do a litmus test. Who is to blame for the Ukraine War? Would you decry the US if they falsely claimed to own most of the Gulf of Mexico and threatened civilian ships? If so, would you also decry China for claiming most of the South China Sea, including waters which are literally closer to other countries than to them?

Every communist is not a tankie. A tankie is someone who defends actions by Russia and China, despite decrying the same actions if the US takes it. I really don't see it as an economic thing at all, although that's certainly where the origin of the word comes from. I see it as someone who thinks everything that the US does is bad, and anything US adversaries do is good. It's a lot more geopolitical in my eyes.

Think of it this way, it's the polar opposite of a nationalist far right conservative when it comes to foreign affairs. Tankies are just one cut away from being the same.