To attack Iran

A unilateral American military attack on Iran would cause incalculable harm to the United States. It would leave the U.S. isolated among the world's nations, it would expose American troops to far greater violence, and it would lay the groundwork for a severe constitutional crisis between the executive branch and an aroused Congress.

Any sensible person can see that, yet the Bush administration seems intent on provoking Iran, with hostile rhetoric, the assignment of an aircraft carrier group to the waters near Iran, and - as reported Friday by The Washington Post - a new policy of killing Iranian agents found to be aiding militias in Iraq. All this, we hope, is only a bit of saber-rattling, but even if that's the case, and the White House has no plans for an attack, it vastly increases the chances that the U.S. and Iran could accidentally stumble into a war.

There are two issues with Iran: its nuclear program and its apparent support for some Shiite factions in Iraq. It would, in theory, be easier to justify an attack on Iran based on evidence it is playing an active role in fighting against Americans, as this might conceivably lie within the bounds of the 2002 congressional resolution giving the president authority to use force in Iraq. It would be comparable to President Richard Nixon's expansion of the Vietnam War into Cambodia. And it would allow for action at any time, as opposed to the years that must elapse before the nuclear threat could materialize.

But Republicans and Democrats in Congress have warned President Bush that they will not stand by and allow such a reckless expansion of the war. We take them at their word. We hope the White House does, too; an invasion or bombardment of Iran would look to all the world like a desperate attempt to salvage the botched war in Iraq, and it would be the height of folly.