The advancement of the Greater Israel project. US taxpayers directly and indirectly funding the regional expansion of a foreign state led by a genocidal maniac, which has no clear benefit to themselves.
Talk of the chaos and stupidity of Trump just obfuscates this grim political reality. Ie, focusing the narrative on political and operational incompetency misdirects the citizenry from the fact that money from their labor that could go to healthcare, education, and building community is diverted to an aggressive foreign entity.