Hasan says that yes, Congress has the ability to remove the disability, but in the past when it did so (after the Civil War) there was never a finding that there had been an insurrection.
I don't think it would have occurred to anyone after a bloody Civil War to make a formal fact finding that there was a rebellion.
Hasan also talks about "concurrent jurisdiction" but it gest murky.
Anyway, Cruz argument 1-B seems to me the easiest way out for SCOTUS, if SCOTUS wants out.
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