What you say here makes sense but it is not at all what is being practiced by some of the "anti-imperialist" left. Max Blumenthal's definition of anti-imperialism begins and ends with America. In his worldview opposing the US and its interests uncritically is the duty of every leftist. If the US supports Ukraine you must oppose it. If the US accuses China of genocide you must support China. If fascists oppose the US government you must side with them too. You must support any and every so-called enemy of the US regardless of what they do or who they are (after all it's all lies from the mainstream media). I am not saying every political commentator should be obligated to report on the abuses of every global power lest they be called "hypocritical", but some leftists will actively defend atrocities as long as they are done in opposition to the US.