Intelligence experts say they're used by terrorists to throw their pursuers off the trail.

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Intelligence experts say the base is still important to Russia but not as essential as it was at the height of the Cold War.

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Whether the error lay with the Central Intelligence Agency or the National Imagery and Mapping Agency, some American experts say the bombing is the result of an overly complex and outmoded intelligence bureaucracy.

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Some experts say screening for emotional intelligence in admissions isn't very smart.

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Maersk's findings are in line with what most experts say -- that intelligence tests are fairly good at predicting people's performance across a range of jobs.

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Even so, experts say Gates is well regarded in Washington intelligence and military circles.

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Hawley and other security experts say a number of factors -- including strengthened cockpit doors, better intelligence and motivated passengers -- has changed the security equation on planes, removing avenues once open to terrorists.

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But experts say that's not necessarily unusual, given the need to protect what the intelligence community describes as sensitive sources and methods.

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Some experts say security improvements since the attacks -- most notably reinforced cockpit doors, better intelligence and motivated passengers -- have made the strict prohibition of small pen-knives unnecessary.

CNN: March 7, 2013 -- Updated 0312 GMT (1112 HKT)

Some security experts say security improvements since the attacks -- most notably reinforced cockpit doors, better intelligence and motivated passengers -- have made the strict prohibition of small pen-knives unnecessary.

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