It was a policy with two targets: the Iranian hawks were to be encouraged to loosen up; and the Western doves were to be shown - if need be - the necessity of being resolute, even to take hawkish actions, convinced that the nicer options had failed.
Obama said the crucial date would be September 2009; he finally began acting at the end of January 2010, so the Iranians got an extra four months. Whether his actions will be effective remains to be seen; the amount of Iranian nuclear development completed under cover of the year given to them is also not yet publicly known.
What is clear, however, is that at least some of the home-team doves have no intention of being swayed by the exercise. For them, any saber rattling by the Americans is wrong, always:
In Iran, after 12 months in office, Obama has got nowhere by making nice. He didn't try that hard. He didn't try for that long. And now it seems the US is reverting to type.
Yes, the Guardian. How did you guess?