“Is” vs. “Should”

Tom Gilson observes the shift that has taken place among those who reject the exclusive claims of the Christian faith:

The world has a big problem with Christian exclusivism—the belief that there is one God uniquely revealed in Jesus Christ, who is the one way, truth, and life for all people at all times. Theologians and apologists have defended exclusivism’s truth since time out of mind, but never so much as in these pluralistic and relativistic times. Recently I’ve come to wonder, though, whether we’re addressing the wrong question; for I am hearing less and less that exclusivism is false, and much more often that it is immoral. The difference is crucial.

I would never dispute the importance of the truth side of the question. I am convinced that Christ is indeed the one way to God. I am equally sure that the truth of this exclusive claim can be defended, and that when someone questions its truth, that’s exactly what we ought to focus on.

It’s just that this is not always the question; in fact in my (limited) experience, it’s no longer frontmost on many people’s minds. It used to be they said, “You believe that Jesus is the one way, but that’s not true.” Now more often they say, “You believe that Jesus is the one way, and there’s something wrong about you—evil, even—for thinking that.”

Or to put it another way: nowadays when people ask themselves, “Should I believe in Christianity?” it’s no longer primarily, “should I believe it on account of evidence or reasons that may support it?” (an epistemic should). Instead it is an ethical “should,” as in, “wouldn’t it be morally irresponsible for me to accept this belief?”

via The Morality of Christian Exclusivism (Part One) » Evangel | A First Things Blog.

Mr. Gilson promises to make a case for the morality of Christian exclusivism, which I hope to follow.

In the meantime, how would you answer those–including virtually all of the “new atheists”–who oppose Christianity on these moral grounds?  Doesn’t–or shouldn’t– “is” trump “should”?   Or is the alleged immorality of Christianity beside the point anyway, given  the theology of the Cross?