Over the last several weeks, there’s been fevered speculation about the likelihood of an attack on Iran’s nuclear facilities before President Bush leaves office in January (Eamonn linked to a couple of the more notable “it’s going to happen” op-eds here.)

Writing in the Washington Post, David Ignatius demurs:

“Though the administration has often been portrayed as divided over military options against Iran, an official denied there are now any sharp rifts. “There is uniformity across the U.S. government about the way to proceed with Iran,” the official said. “Everyone from this White House, including the vice president’s office, is in agreement that the military option is not the best option at this point, and we should pursue diplomatic and economic pressures.”

U.S. opposition to an Israeli military strike now is based on four factors, the official said. First, a strike would retard the Iranian nuclear program without destroying it. (One intelligence estimate is that an attack would delay the Iranians by just two months to two years.) Second, a strike would rally support for the unpopular government of President Mahmoud Ahmadinejad when he faces growing economic difficulty. Third, an attack would undermine U.S. policy in Iraq, when the United States appears to be making some progress, and in Afghanistan. And, finally, a strike against Iran, as with any military action, would have unpredictable consequences.

In evaluating the Iranian nuclear threat, the United States and Israel are using different intelligence. U.S. analysts believe Iran can’t produce a bomb before the end of 2009 and probably not until the 2010–2015 time frame, according to a senior U.S. intelligence official. The Israelis, however, fear that Iran could enrich enough uranium for a weapon sometime next year. By late 2009, the Israelis warn, the Iranians could produce the 1,000 kilograms of low-enriched uranium that could quickly be converted to the 25 kilos of highly enriched fuel needed for a bomb.”

The crunch will come next year, Ignatius concludes, “when there are new governments in Israel and the United States — and a volatile presidential election scheduled in Iran. For now the United States and its allies, including Israel, seem willing to pursue the diplomatic track. But if that doesn’t work — and there are no signs yet that Tehran is willing to bend — all the deadly options will remain on the table.”