THE US: Last night's security alert in the US was the first time US officials had compared the scale of a possible attack to the devastation wrought on New York, Washington and Pennsylvania by al- Qaeda. The security alert status has vacillated between yellow and orange since the code was established last year.
The Homeland Security Secretary, Mr Tom Ridge, warned Americans last night about the possibility "in the coming days and weeks" of "near-term attacks that could either rival or exceed what we experienced on September 11th".
The choice of language appeared aimed at catching the attention of a public which has been suffering from "alert fatigue".
The last time the threat code was raised to orange was May 20th, after a string of suicide bombings in Saudi Arabia and Morocco, blamed on al-Qaeda. The raised alert lasted 10 days.
In March in the run-up to the invasion of Iraq, Washington put the country on the second-highest alert level, after President Bush told Iraqi President Saddam Hussein he had 48 hours to go into exile to avoid war. It returned to yellow on April 16th.
In February, the Department of Homeland Security raised the alert level to orange, responding to reports that al-Qaeda might attempt to attack Americans in the United States or abroad in or around the end of the haj, the Muslim religious period ending in mid-February.
It was lowered again on February 27th.
It was unclear last night whether the decision to raise the state of alert was connected to a broadcast on Friday on the Arabic television network al-Jazeera; the station aired an audio tape of a statement attributed to Ayman al-Zawahiri, Osama bin Laden's deputy and an Egyptian-born al-Qaeda strategist.
"We are still chasing the Americans and their allies everywhere, even in their homeland," Mr al-Zawahiri said on the tape.
In the past, such broadcasts have preceded al-Qaeda attacks, and US intelligence officials believe they could be used as a signal to al-Qaeda cells around the world, or as an attempt to gain credit for the attacks by demonstrating prior knowledge.
Mr Evan Bayh, a Democratic member of the Senate Intelligence Committee, told CNN yesterday: "The greatest risk is probably abroad, but they would like nothing better than to have an attack here at home."
Gen Richard Myers, the chairman of the US joint Chiefs of Staff, told America's Fox television yesterday: "There is no doubt, from all the intelligence we pick up from al-Qaeda, that they want to do away with our way of life.
"And if they could cause another catastrophic event, a tragedy like 9/11, if they could do that again, if they could get their hands on weapons of mass destruction and make it 10,000, not 3,000, they would do that, and not just in the United States but in any of the free world or any peoples that treasure their freedom.
"So we take all these intelligence tips very, very seriously."
- (Guardian service)