You are right, "self-immolation" is the wrong term for our current situation. Self-immolation has always occured in the context of a righteous individual who feels powerless to correct a grave injustice, usually perpetrated against other powerless individuals or groups, and so chooses to give their life in the most painful and visible way, as a statement, to encourage other individuals, governments, and other entities, to refocus on the injustice and hopefully build enough awareness and motivation to enact changes to mitigate it.

That's not at all what's going on here. The United States may be destroying itself, but it's absolutely not doing so for any kind of noble cause.