Writing in the Wall Street Journal, Danielle Plekta suggests that the only choice the Obama administration faces on Iran is war or managing the risks of a nuclear Iran. Sounds about right to me. While I don't know how soon Iran will actually acquire a bomb or whether they want to create a Japan-style capacity to build one quickly if they want, I think it's reasonable to assume that this the direction we're headed.
And whichever option you favor - containment or war - the inevitable outcome is to draw the United States deeper into the Middle East. No wonder China's feeling confident.