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Here's the simplest, most obvious question you never bothered asking Ayers:
"Yes or no, do you specifically regret committing and planning to commit acts of violence?"
Instead, you let Ayers blather vague, undefined, unspecified notions of regret, which he's already done in numerous venues. If you couldn't pin him down on the crux of the matter because of your personal relationship with him, you should have recused yourself.
You still have his phone number, why not call him up and ask him that one follow-up? Ayers has managed to dodge that question with several other journalists, you could still get a scoop.
Or is that not your actual goal?