Because of America's high taxes, America's minimum wage laws and America's ludicrous environmental regulations.
Also its crushing import/export bureaucratic burden, its crushingly complex tax system and its byzantine legal system.
Also: America owns the world strategic reserve of a) lawyers and b) people who are owed a living by Whitey.
What did I miss?
My comment assumes that - should things “go south” - we would take care of the issues you mention (the lawyer issue would probably be the most difficult IMO - for a variety of reasons).
Not saying this would happen, but it would provide the opportunity to, in effect, start over.
Our defense budget, which exceeds the rest of the world's, combined.