There seems to be some pushback to Obama's claim that the US is not a Christian nation. There are a number of different senses in which one could take his statement; in some of them it is true and in others it is nonsense.
But the complaints I've seen completely overlook his audience: Turks. In the Middle East there are only 3 nations which have secular governments: Israel, Lebanon, and Turkey. And Turkey is sliding back into that Islamic prison. Of course Obama's going to emphasize the secular nature of the US, if he's been given any sane guidance at all about what to say in Turkey. And he'll make believe that Muslims form a noticeable and important part of the nation--because it plays well with the Turks, whose view of the US is warped by the Middle East media. This stuff isn't meant for US consumption.