John Cassidy in The New Yorker on Snowdon and the press, including Josh Marshall (see Bertram).
Marshall responds

Some of this actually connects up with what I’ve written about ‘thick citizenship' and my critique of dual-citizenship. I think our equality and shared community as citizens rests on our citizenship being more than a matter of travel documents and accidents of birth.

Marshall defends the US, not as a republic, but as such.
His arguments for citizenship, in context, here.  With all his mocking of Republicans on racism and DOMA etc. his blindness is almost complete.

google site search, talkingpointsmemo.com: "white people"

I'd never read Marshall's original post on Snowdon, and in fact on Manning as well. It's impressive.