Probably to directly oppose the "special operation" description given by Russia. "full-scale invasion" implies use of massive/regular force and conventional military conquest, which is the thing that is actually happening. Whereas the "special operation" would imply a small scale attack that has a much more specific and narrow goal.

You could argue that it genuienly started as such since Russia tried to do a surgical attack and blitzkrieg Kiev. But the moment that plan failed and the concepts of "frontlines" and "captured territories" started to apply, it became a "full-scale invasion".

Naturally. Why would they outlaw their allies? As long as neo-nazis fuck with capitalism, they don't care. What's a little genocide? The money engine needs to keep turning.

Just when you think there's at least one or two politicians in the US who are not openly genocidal fucking maniacs...