I hope this author was being funny, rather than serious when he wrote that he didn't understand Duncan's motivations.
Arne Duncan is a politician, a Chicago Politician. He attacks Texas, because Texas is a big red state. The Obama machine have the red/blue map cemented in their brains, and all thoughts, utterances and actions are reflective of what color state they are addressing. They do not feel a part of the entire United States, but look on states with Republican governors, or states that voted for a Republican in the White House as their enemies. I am not exaggerating.
I have heard him say unbelievably stupid remarks about the improvements in student test scores which occurred "for the first time" after Obama was elected. The man is either a bold-face liar (typical dem), or delusional.
I think you filled in what the author knows and you did it nicely.