I'm somewhat of a zealot when it comes to attacking the use of the term "Judeo-Christian", which I think inaccurately lumps together two very different religious traditions. Sometimes my critique is thus on the general usage, and other times it's about particularly inane applications.
John McCain, apparently, likes to use "Judeo-Christian" a lot. And if the Boston Globe's coverage is at all reliable, his usage would seem to fall definitively in the latter category -- warning a New Hampshire crowd that Iranians "sure don't share our Judeo-Christian values."
Yes, let's undercut eight years of trying to persuade Muslims that this isn't a Holy War. As the Globe reports, McCain continually uses "Judeo-Christian" as a synonym for "freedom" or the American way, a conflation which is (a) wrong, (b) excluding of millions of Americans, and (c) obviously won't play well in the Muslim world. If Muslims believe that our quest to "stand up for freedom" is literally a desire to impose our own religious tenets on them, well, let's just say it makes our job a wee bit tougher.
Meanwhile, returning to my general critical stance, the Globe hedges a little bit in the middle of its piece when it says that "The term Judeo-Christian has a benign history," continuing to claim that "It was popularized by liberal groups in the 1920s and 1930s to forestall anti-Semitism."
Now, I'm not sure that's accurate (I seem to recall that the term was actually originated by mocking anti-Semites, but I could be wrong and/or it could have been appropriated later by liberal groups), but that's besides the point. The point is that "Judeo-Christian" is not benign. It represents, if anything, the bad sort of liberalism which conditions equality on uniformity -- in this case, replacing a unique Jewish heritage with insinuations that Judaism is just a sub-species of Christianity. I'm willing to grant that the non-Jewish speakers who promoted "Judeo-Christian" may have had their hearts in the right place, and I'm willing to grant that Jewish speakers who did the same may have seen that strategy is the best available in the face of anti-Semitic oppression. But it remains true that it is a term adopted under duress, and ultimately is not an accurate expression of the history, experience, or interests of the Jewish community. In that way, it is the furthest thing from benign.