Nobody has stopped the negotiations. In fact, if the US were directly involved they would be more likely to fail. It is better to have the US as seen to be in opposition in this case.
Allowing the press and a few diners to label the President of Iran as a "madman" simply isn't a large enough deal to say we have sidetracked and stopped negotiations. It is unrealistic to expect our government to crack down on those so labeling this man...
In fact, if the US were directly involved they would be more likely to fail.
This I agree with. Bush and Condi are utter failures, and completely discredited.
We would need somebody like a Colin Powell, and James Baker, or a Richard Holbroke. Somebody tough and competent.
Hell, even Ronald Reagan has the gravitas and credibility to sit down for tough face to face negotiations with the evil empire.