America A 'Muslim Country?'

So, President Obama says we are not a Christian nation (even though America is 85% Christian) and we are not a Jewish nation (even though there are more Jews in America than there are in Israel) but we do nonetheless seem to be a "one of the largest Muslim countries in the world."
What?!? . . . What's going on here?

From the Weekly Standard:

As we noted earlier, and as ABC now confirms, Obama's speech in Cairo focuses on his Muslim roots and the unique perspective it provides him. Obama also teased the contents of the speech in an interview with a French television station:

What I want to do is to create a better dialogue so that the Muslim world understands more effectively how the United States but also how the West thinks about many of these difficult issues like terrorism, like democracy, to discuss the framework for what's happened in Iraq and Afghanistan and our outreach to Iran, and also how we view the prospects for peace between the Israelis and the Palestinians.

Now, the flip side is I think that the United States and the West generally, we have to educate ourselves more effectively on Islam. And one of the points I want to make is, is that if you actually took the number of Muslims Americans, we'd be one of the largest Muslim countries in the world. And so there's got to be a better dialogue and a better understanding between the two peoples.