The US National Intelligence Estimate (NIE) on Iran's nuclear intentions is the political version of a tactical nuclear strike on efforts to prevent Iran from acquiring nuclear bombs.

The NIE begins with the sensationalist opening line: "We judge with high confidence that in fall 2003, Teheran halted its nuclear weapons program." But the rest of the report contradicts the lead sentence. For instance, the second line says, "We also assess with moderate-to-high confidence that Teheran at a minimum is keeping open the option to develop nuclear weapons."

Indeed, contrary to that earth-shattering opening, the NIE acknowledges that the Iranians have an active nuclear program and that they are between two and five years away from nuclear capabilities.

The NIE's final sentence: "We assess with high confidence that Iran has the scientific, technical and industrial capacity eventually to produce nuclear weapons if it decides to do so," only emphasizes that US intelligence agencies view Iran's nuclear program as a continuous and increasing threat rather than a suspended and diminishing one.

But the content of the NIE is irrelevant. The only thing that matters is the opening line - as the report's authors no doubt knew full well when they wrote it. With that opening line, the NIE effectively takes the option of American use of force to prevent Iran from acquiring nuclear weapons off the table.

There are two possible explanations for why President George W. Bush permitted this strange report to be published. Either he doesn't wish to attack Iran, or he was compelled by the intelligence bureaucracy to accept that he can't attack Iran.

Arguing the former in Time magazine, former CIA agent Robert Baer explained, "While the 16 agencies that make up the 'intelligence community' contribute to each National Intelligence Estimate, you can bet that an explosive 180-degree turn on Iran like this one was greenlighted by the president."

The alternative view - that Bush was forced to accept the report against his will - is also possible. The report's primary authors, Thomas Fingar, Vann Van Diepen and Kenneth Brill are all State Department officials on loan to the office of the Director of National Intelligence. According to the Wall Street Journal, all three are reputed to be deeply partisan and hostile to Bush's foreign policy goals. Furthermore, for the past four years the three have reportedly worked studiously to downplay the danger of Iran's nuclear weapons program and to discredit their opponents within the administration.

Thursday The New York Times ran a story detailing the process in which the NIE was collated that lends credence to the view that Bush was compelled to accept it. According to the Times, in the months preceding the NIE's publication, Mike McConnell, the Director of National Intelligence, purposely prevented the White House from seeing any of the raw intelligence data on which the NIE's radical conclusion on Iran was drawn. This alone indicates that the intelligence community may well have presented Bush with a fait accompli.

But it really doesn't make a difference one way or another. Whether the president agrees or disagrees with the NIE, he is boxed in just the same. The NIE denies him the option of taking military action against Iran's nuclear program for the duration of his tenure in office. So for at least 14 months, Iran has nothing to worry about from Washington.

And the NIE's political repercussions extend well beyond the current administration. Today, no Democratic presidential candidate will dare to question the opening line of the report. The Democratic Congressional leaders are demanding that the administration immediately open bilateral talks with Iran. And Senator Hillary Clinton is being pilloried by her party rivals for her Senate vote in favor of classifying the Iranian Revolutionary Guards Corps as a terrorist organization.

The situation among Republicans is not much more encouraging. Although Republicans have greeted the NIE with grumbling rather than glee, it is hard to imagine any of the Republican presidential candidates taking issue with its opening line. Doing so entails the risk of being accused of alarmism and warmongering.

Although Bush and Secretary of State Condoleezza Rice continue to speak of imposing further sanctions on Iran, the fact is that after the report was published, any chance of getting an agreement on further sanctions evaporated. French President Nicholas Sarkozy stands humiliated for having dared to speak of the possibility of attacking Iran. The Germans will immediately reinvigorate their commercial ties with the mullahs as will the British and the French. The Russians and Chinese will drop even the veneer of opposing Iran's nuclear program.

The NIE makes light of Iran's acknowledged nuclear capabilities by intimating that Iran's intentions are not necessarily hostile. Yet, it gives no evidence that this is the case. Rather, the NIE projects the aspirations of its American authors on the Iranians. But since one's actions rather than the hopes of one's adversaries are the best indication of one's intentions, the only conclusion that can be reasonably be drawn about Iran is that its intentions are anything but benign.

For instance, Agence France-Presse reported that in 2005 Iran bought 18 Russian SS-N-6 ballistic missiles from North Korea. The North Koreans had modified the missiles, which were originally submarine-launched, to enable them to be launched from land-based mobile launchers and renamed them BM-25s. What is notable about these missiles is that the Soviets designed them specifically to carry one megaton nuclear warheads.

As the on-line intelligence newsletter NightWatch noted this week, "Curious minds want to know why would Iran buy such a system from North Korea in 2005, if it had abandoned its nuclear warhead program in 2003?"

Beyond that, the NIE makes a strange distinction between Iran's "civilian" nuclear program which has not stopped for a moment and its "military" program which supposedly ended in 2003. Since both programs are controlled and run by the Revolutionary Guards, it is obvious that no such distinction exists for the Iranians. And as former US ambassador to the UN John Bolton wrote Thursday in The Washington Post, "It has always been Iran's 'civilian' program that posed the main risk of nuclear 'breakout.'"