It seems to me that Hersh is a journalist who collects information, maybe some from open sources, this latest article clearly relies mainly on "off the record" encounters and a fair degree of lobbying for 'X' via Hersh himself. His art is in assembling this in a readable chunk.

Now who are the intended target readership? I am sure his editor primarily considers the target readership to be those who subscribe to the paper. Hersh may consider the target to be somewhat wider, maybe even those who actually make the decisions in this policy area.

Hardly worth vilifying him or more. As for being a threat to national security I doubt he is even in the 'Top 100'; a threat IMHO to vested interests? Yes. national security is not the same as political and institutional embarrassment.