Not really a tough call for me to say that Rand trumps Greenwald. (Greenwald is right, though, that Obama has become an empty suit after presenting such a promising and principled-sounding persona during the '08 campaign. Fool me once....) America as it is right now - in all its intellectually-stunted glory - is not obviously exceptional, even if it is still exceptional compared (in full context) to the alternatives. But America as it might be and ought to be? Of course it's exceptional. It's all about individualism and a benevolent sense of life. (America is also uniquely situated to boldly lead the world toward the Singularity. Ain't integration fun?)
To see that as clearly as Rand did or yours truly does, requires a massive amount of well-focused integration - e.g., a well-integrated understanding of Galt's radio address. Attaining such an integrated understanding is not at all quick or easy (if it were, everyone would be doing it), and the leads (e.g., this) are not at all obvious or accessible. Without the requisite context of understanding, Rand's words - about America, or just about anything else - fall on uncomprehending and/or cynical ears.
Hence the assignment at the end of my previous posting.
"Let your mind and your love of existence decide."