Note:
(a) If VOA wants to know whether defense secretary Carter put off a visit to Beijing, why doesn't it ask US Department of Defense? I can only think of 丁学良's speculation: "另外一种可能性，根据以前的惯例，他在访问以前，协商提出一些条件，希望中国官方做哪些事，讲哪些话，或者不做哪些事，不讲哪些话。也许在这些很关键的沟通环节上，中国政府很明确的告诉他这是没有办法达到你的希望的。" Then, why doesn't VOA ask somebody in Beijing. After all, professor 丁 is in Hong Kong, far away from gossip in Beijing. I doubt 丁 knows more than you or I.