What I asked was why Dreier did wrong in mentioning his job and place of employment in his letter. Your answer seems to be that his employer is tax-exempt.

But if you are right, then an employee of the Red Cross would be doing wrong to mention that fact in a post on his blog.

Do you accept this implausible consequence of your view?

"[Dreier] identifies himself as an Occidental College professor in the memo – in fact, he ensures that everyone knows that he is the renowned “E.P. Clapp Distinguished Professor of Politics, Director of the Urban & Environmental Policy Program, Occidental College.”"

I'm curious why you think this is wrong, Kurt. How does it differ from the perfectly acceptable mention of your US army service in your bio on this site? In both cases, a biographical fact about an author increases his credibility in the eyes of the target audience.