Some interesting testimony from an FBI interrogator in the trial of Osama bin Laden’s driver, Salim Ahmed Hamdan.

GUANTANAMO BAY, Cuba, July 23 — Osama bin Laden’s driver witnessed the al-Qaeda leader being briefed on the day of the Sept. 11, 2001, attacks and overheard him express satisfaction that the death toll had exceeded expectations, an FBI interrogator testified Wednesday.

Salim Ahmed Hamdan, now held at the U.S. military prison here, had said under questioning six years ago that bin Laden was “happy about the results” of the terrorist strikes because he had expected “only” 1,000 to 1,500 people to die, former FBI agent Ali Soufan told jurors at Hamdan’s military trial.

During the 2002 interrogation, Hamdan “said he had heard bin Laden saying he didn’t expect the operation … would be that successful,” Soufan said. Nearly 3,000 people perished in the attacks on the World Trade Center and the Pentagon.

Hamdan, who is charged with participating in a terrorist conspiracy, is the defendant in the first U.S. military commission held since World War II.

According to Soufan, Hamdan said that on Sept. 11, 2001, he was present for a meeting in Kabul, Afghanistan, between the al-Qaeda leader; his deputy, Ayman al-Zawahiri; and Khalid Sheik Mohammed, the self-described mastermind of the assault on the World Trade Center and the Pentagon. As the men viewed pictures of the 19 suicide hijackers, bin Laden “praised them and their courage and asked God to accept them as martyrs,” Soufan quoted Hamdan as saying.