The old and new worlds of intelligence met on Sept. 11, when terrorists attacked the World Trade Center and the Pentagon.
Terrorism is an old-world problem in new-world circumstances. The new world is much more open, with vast amounts of information, much of which is neither owned by US intelligence agencies nor can be regarded as reliable - for example, that stew of fact, fiction, and disinformation known as the Web.
Openness needs to be put at the heart of the intelligence business. Exploiting secrets used to be the stock in trade of intelligence. But now the task is wider: gathering and sifting through a flood of information. This changed world requires a fundamental reshaping of the intelligence business.
Terrorists, however, are not part of the new openness. They do not advertise their plans, so the intelligence agencies' special sources are still important - espionage, or human intelligence (HUMINT), intercepted communications or other signals (SIGINT), and photos or other images (IMINT). Yet, even to grapple with terrorism, methods from the old world need to be reshaped by the circumstances of the new.
The CIA needs to conduct espionage in a very new way - more tightly targeted and operating mostly independent of US embassies abroad. Spying will also have to be a more "cooperative" venture. American spy-masters will seldom be able to crack into terrorist cells, but other countries, including those that are not friends of the United States, may be more able to do so. Already, US intelligence is working with Sudan, despite its inclusion on Washington's list of terrorist sponsors.
Spying is most valued for solving immediate, tactical puzzles - such as, what is Osama bin Laden planning? These puzzles have a solution, if only we had access to the information. Puzzles were intelligence's stock-in-trade during the cold war: How many missiles does the Soviet Union have? How accurate are they? What is Iraq's order of battle?
Puzzles' opposites are mysteries, questions that have no answer even in principle: Will North Korea keep its part of the nuclear bargain? Will China's Communist Party cede primacy? What will Mexico's inflation rate be this year? The mystery can only be illuminated; it cannot be "solved."
Spying, however, is a target-of-opportunity enterprise. What spies may hear or steal today, or be able to communicate to their American case officers today, they may not hear or see or be able to get out tomorrow. What is decisive today may be unobtainable tomorrow. Worse, the crisis moments when information from spies is most valuable to us may be precisely when they are most exposed, when to communicate with them is to run the greatest risk of disclosing their connection to us.
Secrets are more valuable with regard to enduring puzzles, ones that will still matter tomorrow if they are not solved today. A foreigner's negotiating position is a perishable secret; after today's round, the US negotiator will know it. By contrast, the order of battle for the Iraqi military is an enduring puzzle: Whatever we know today, another puzzle piece will always be welcome tomorrow.
The required reshaping of the CIA's clandestine service, the spy-masters, goes well beyond what is imaginable in today's political climate. Indeed, today's first answer - more money - is exactly what is not required.
First, espionage should be narrowed to focus on potential foes of US troops abroad, the governments of a small number of potentially destabilizing states, and groups that threaten terrorist activities against the US.
Second, this streamlining means that the CIA would no longer have stations everywhere around the globe. There is merit to the counterargument - that our untidy world makes it impossible to predict where the US will want to act, and so some infrastructure for spying should be sustained almost everywhere. But on balance, the risk of such a far-flung presence outweighs the gain.
Third, the reshaped clandestine service would operate from the US and through case officers abroad, outside embassies, under nonofficial cover. Operating under official cover is paper thin in any case; what it mostly supplies is diplomatic immunity, thus lowering the risk to CIA spies, should they be caught by local counterintelligence.
During the cold war, when the CIA's targets were Soviet officials anywhere and officials and politicians from the local country, the diplomatic cocktail-party circuit was not a bad place to troll for recruits. But terrorists or Colombian drug-cartel leaders aren't likely guests on the embassy circuit.
Cracking the hardest targets, like terrorist cells, is very painstaking and chancy business. Other countries, those closer to the terrorist organizations, including countries that are not US "friends," may have better luck. The US will need to work with them.
Gregory F. Treverton is senior policy analyst at RAND and senior fellow at the Pacific Council on International Policy. His book 'Reshaping National Intelligence for an Age of Information,' from which this article is adapted, was published earlier this year by Cambridge University Press.