While the path ahead remains enormously difficult, word from Secretary of State Condoleezza Rice and President Bush that the United States is open to direct talks with Iran marks a major and positive change in U.S. attitude.

The offer of direct talks was linked with a demand that Iran first suspend its uranium-enrichment activities, a demand that Iran quickly and firmly dismissed.

That initial reaction may have been in part a tit-for-tat reaction to the dismissive way in which Rice and Bush reacted to an earlier direct letter to the president from Iranian President Mahmoud Ahmadinejad.

Categorize all that as posturing. What is important is that after weeks of discussion within the White House, the United States has publicly said it is willing to join direct talks with Iran.

This responds to many official and unofficial signals from Iran that it also wants talks as a way out of the standoff between the two countries. It also signals that, at least for the moment, the United States is serious about a diplomatic way out of this mess.

The shift in U.S. policy came on the eve of Rice's trip to Europe to meet with the so-called EU-3 — Germany, Britain and France, which have been lead negotiators with Iran to date.

The three, with U.S. participation, have put together a package of sanctions and incentives designed to get Iran to back off its nuclear program. That offer, formally announced Wednesday, offers two paths forward for Iran: confrontation or negotiation.

The path of negotiation looks more promising after the latest White House statements. That's particularly so in contrast to an extended period of hard-line comments that left many doubting whether the United States truly had any interest at all in a diplomatic solution.

As Rice was the first to admit, this is only an early and tentative step toward a warming of feelings between the two sides. The uranium-enrichment issue aside, she noted, the two have serious differences on matters ranging from Iran's support of international terrorism to its backing of violent insurgents in Iraq.

But it is a start, and a most important one at that.