"America is unable to win the wars she chooses to fight. She cannot or will not control and defend her borders from a mass migrant invasion. She cannot halt an outbreak of criminality and killing in her great cities. She has not run a trade surplus in four decades. Her dependency upon foreign producers is unprecedented. And her budget deficits continue to break records every year — as does her soaring national debt. Is that not the description of a failed or failing state?"
Read his rationale here; https://buchanan.org/blog/is-america-becoming-a-failed-state-149897