Same Iranian government as a year ago, as determined as ever to attain nuclear-weapons capability. Same U.S. government as a year ago, as determined as ever to keep nuclear-weapons capability out of Iran’s grasp.

Same essential facts, too. Iran is developing the capacity to enrich enough weapons-grade uranium for bombs. If anything, it has accelerated its efforts.

Yet everything has changed. A year ago, U.S. military action against Iran’s nuclear program seemed very much “on the table,” perhaps before President Bush left office; now the possibility seems remote. The reason is not a new fact but a new sentence:

“We judge with high confidence that in fall 2003, Tehran halted its nuclear weapons program.”

Those were the opening words of a National Intelligence Estimate that the Bush administration abruptly declassified and released in December. The world read: “Tehran halted its nuclear weapons program,” and the wind shifted into Iran’s sails.

The assessment went on to note, “Tehran at a minimum is keeping open the option to develop nuclear weapons.” Once Iran has weapons-grade uranium, building actual bombs will be little more than a formality—which is why the real problem remains, as it always has been, stopping Iran before it gets that far.

In short, the threat did not change; only the perception of the threat did. But threat-perception, in foreign policy, often matters more than threat-reality. Just ask an Iraqi.

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