Diplomats may want to share opinions on their counterparts from other nations that are legitimate (e.g., even somewhat innocuous stuff like ... we don't think they're truthful, they have not kept their word before, they don't have the support of their people, they are bluffing, our negotiation strategies, etc.). This is stuff that we need to be able to share confidentially within our own government and intelligence organizations that would harm our ability to deal with other countries ... I don't see how publicizing this can be construed as "good". I understand that not all of this information is harmful, but I sure do see how this kind of thing could jeopardize our country's effectiveness and security.