Most excellent analysis! I guess most of it boils down to getting rid of the bloody labor unions.
And the damage done in the past. I left out factor #4: The cost of paying gigantic pensions and health care to retired workers, whose powerful unions extorted ridiculous benefits in the 1960s and 1970s.
Again, the Chinese and new companies don't have this to contend with. (Ironically, if rates of smoking had stayed constant, the American steel companies might be okay. All those retired workers were supposed to die off a lot sooner.)