I expect S&P to confirm the USA's AAA, with a negative outlook

Now that both Moody’s and Fitch have affirmed the AAA, I consider it quite unlikely that S&P will go out on a limb and unilaterally rate Treasuries at AA+. I remember when Moody’s took Japan to A2, it made the rating irrelevant in both domestic and foreign currency. Maverick positions hurt credibility (see: Central Banks, the IMF).

The US remains a benchmark standard for “risk free”. The ceiling deal should result in a less frightening fiscal trajectory over the medium term. Therefore, it would be premature to downgrade before the process plays out in December.

I expect more threatening language, a negative outlook, but no downgrade.