Just how much should the public be told about threats to specific targets?
By Paul Reynolds
BBC News Online world affairs correspondent
Security has been stepped up at the World Bank in Washington
The authorities face a dilemma. The public wants to know the risk uncovered by intelligence but how much does it need to know about the source of that intelligence?
Alerting the public can have the benefit of deterring an attack. But revealing the source of the information can put at risk the acquisition of more information.
It is an old problem, and one made more acute by the revelations about the weakness of intelligence over Iraq. These days, the public is more sceptical. And it wants to know more.
The Sunday warning
The issue has been raised by the sudden warning issued on Sunday that al-Qaeda might be planning to attack five major financial offices in the United States.
The alert level in some districts in the cities named, New York, Washington DC and Newark, was raised to orange, the second highest of the five-level system. Barriers went up, police patrolled, employees were checked.
The fear level as well as the alert level went up.
Yet it emerged on Monday that al-Qaeda carried out the surveillance on these buildings several years ago, with most of it done, according to US media reports, before the attacks of 11 September 2001.
However, intelligence sources added that the information was updated in January this year, though exactly how detailed and active that updating was is not being made known, beyond a suggestion that it involved a photo of a building other than the ones named.
It is also possible of course that there is some undisclosed source of intelligence, warning of an attack. Indeed, the New York Times on Wednesday quotes a White House official as saying exactly that, without giving details.
The American public had not been told, though, how old the information was. It emerged only through media interviews with unnamed intelligence sources. This leaves the public uncertain as to the nature of the threat.
What Tom Ridge said
This is what the Homeland Security Secretary Tom Ridge said publicly at a briefing for reporters on Sunday afternoon:
"As of now, this is what we know: reports indicate that al-Qaeda is targeting several specific buildings, including the International Monetary Fund and World Bank in the District of Columbia; Prudential Financial in Northern New Jersey; and Citigroup buildings and the New York Stock Exchange in New York."
The word "targeting" is of course a bit ambiguous. It does not necessarily mean that an attack is actively being planned though it does not exclude that. But Mr Ridge did use the present tense in saying "is targeting."
Mr Ridge might argue that he was being truthful. But it was not, it appears, the whole truth.
What the president said
The next day, President Bush, in announcing his agreement to the appointment of a National Intelligence Director, did not go into the background either.
He simply said: "I think we have an obligation to inform the people involved with protecting New York City, in this case, or parts of Jersey, or parts of D.C. about what we know. We have an obligation. When we find out something, we've got to share it. What we're talking about here is a very serious matter based upon sound intelligence."
What that "sound intelligence" was he did not explain.
Open to political charge
But not sharing, to use the president's word, as much as it knew, the administration leaves itself open to charges that it is manipulating public fear for political reasons during an election campaign.
This question was asked of Frances Fragos Townsend, the Deputy National Security Advisor for Combating Terrorism on Monday.
She replied: "It had absolutely nothing to do with the Democratic National Convention. The source of the intelligence was - there were multiple reporting streams that came together in such a way to give us real, grave concern."
What the intelligence said
It has now emerged that the intelligence (which Mr Ridge rated 10 out of 10) was regarded as very sound but most of it was also a bit dated.
It came from computer and other records found after the recent arrest in Pakistan of several al-Qaeda operatives.
The records referred to detailed surveillance of the buildings, obtained by the use of couriers, for example, to get inside. Even the number of passers-by at any one time was measured.
One senior US government official justified the warning in a comment quoted by the Washington Post: "Al-Qaeda collects, collects, collects until they're comfortable. Only then do they carry out an operation. And there are signs that some of this may have been updated or may be more recent."
Mr Ridge took the same line when he spoke to New York business people on Monday.
Al-Qaeda's modus operandi
It is true that al-Qaeda is methodical and patient in its planning and collection of information. But in its previous operations, the actual attack was also preceded by active and up-to-date observations.
The suspected leader of the Madrid bombing is reported to have told an associate that he had been planning the attack for two and a half years.
The 11 September hijackers were first sent for training in 1999, almost exactly two years before, according to the report of the recent Commission on the attacks.
Both attacks would not have have taken place without up-to-the minute checks.
So were the records uncovered in Pakistan evidence of a previous operation which was abandoned or signs of an imminent threat?
The fact is that nobody really knows.
The US authorities had no choice about whether they revealed that there was a threat.
They did have a choice about whether to reveal the nature of the threat.