In comments in that last post, William Hallowell pointed to the Foreign Affairs/Public Agendas' Foreign Policy Index. It shows that the American public wants a diplomatic solution in Iran, and that there's a growing preference for diplomacy over military action in general.
It also shows that public anxiety over America's place in the world is rising fast- it's already at 137 on their 200 point scale, scraping the edge a full-blown crisis of confidence. Not a big surprise, but definitely a big problem.
(The download link for the report itself. I'll get into it more when I have a chance to read through it.)