With the publication of formerly secret documents that shed light on how the war in Afghanistan is going, one thing is clear: Americans need a better explanation of our nation’s presence there.

The reason that the current administration has given for the war in Afghanistan amounts to two words, “national security.” But as Americans get behind-the-scenes looks at what is really going on in that war, it becomes increasingly difficult to understand how our security is being protected — and, specifically, how our troops’ sacrifices are being put to good use. It certainly does not seem like we are any nearer to capturing key Al Quaida figures today than we were a half-dozen years ago. Nor does it seem the region will remain stable if our troops were to leave. We can hope that there is more to the matter than is apparent to a typical observer; but we can not know that unless our leaders provide a clear — and accurate — explanation of what they seek to gain and how.

It’s a good time now, as questions fly, for the president to speak to the nation not only about what is going on in Afghanistan, but about why it will serve American interests to continue fighting there.