In 2002 and 2003, in making the case for a war with Iraq, the president and his team would frequently tell Americans that we couldn’t wait for actual proof to justify an invasion, because the “smoking gun could be a mushroom cloud.”

In 2007, in describing a possible confrontation with Iran, Bush has decided to be even less subtle.

The United States demanded Tuesday that Iran end any support for extremists in Iraq “at once” and raised the specter of a “nuclear holocaust” in the Middle East if Tehran gets atomic weapons.

US President George W. Bush branded the Islamic Republic “the world’s leading state sponsor of terrorism,” citing its backing of Hamas, Hezbollah, Palestinian Islamic Jihad and Shiite fighters killing US troops in Iraq.

“And Iran’s active pursuit of technology that could lead to nuclear weapons threatens to put a region already known for instability and violence under the shadow of a nuclear holocaust,” he told the American Legion veterans group.

“Iran’s actions threaten the security of nations everywhere, and the United States is rallying friends and allies to isolate Iran’s regime, to impose economic sanctions. We will confront this danger before it is too late,” he said.

It's like deja vu all over again.