There is a distinct difference between wars based on territorial expansionism and civil wars. When one country invade an other for territorial gain, it is fairl

There is a distinct difference between wars based on territorial expansionism and civil wars. When one country invade an other for territorial gain, it is fairly easy to identify an aggressor and a defender. With a civil war you got factions within a country fighting for control. The start of the conflict tend to be different. In an invasion you got an external force starting the war by sending in troop and initiating the conflict, and you got a clear defined border of conflict that starts out at the border and then fans out. The capital tend to be attacked at a late part of the conflict, unless it is located directly at the border. In a civil war the war generally breaks out at multiple places from within, usually in the capital where the existing seat of power is located. The conflict border is generally unclear and fighting occur at multiple locations all over. Invasion also tend to have a history of territorial disputes about where the border between two nations should be drawn. Civil war on the other hands tend to have a history of demographic nature, where different groups within a country are fighting for control of the country. In terms of public support, especially since world war 2, invasions that has aim of taking territory is generally feared. If they invade Ukraine today in order for Lebensraum, then what is to say that Poland will not be next for the exact same purpose? Which country can ever feel save when a larger nearby country starts to invade others for the purpose of taking territory? Civil wars on the other hand is a human tragedy, but the factions fighting inside Yemen doesn't have a reason to make Poland the next target. It not so much of a double standard but rather human priority of things that feel threatening to themselves.