Khaled Abdullah / Reuters file Tribesmen stand on the rubble of a building destroyed by a U.S. drone strike in the southeastern Yemeni province of Shabwa. Abdulrahman al-Awlaki, the 16-year-old son of slain U.S.-born cleric Anwar al-Awlaki, and six al Qaeda militants, were killed in a strike on this building on Oct. 14, 2011, tribal elders said.

The former top lawyer for the Pentagon said Thursday that any official involved in counterterrorism should have a “heavy heart” after reading a grandfather’s moving account of the inadvertent killing of his grandson in a U.S. drone strike.

Jeh Johnson, who served as general counsel of the Defense Department until last year, reacted strongly to a New York Times op-ed published Thursday about the slaying of 16-year-old Abdulrahman al-Awlaki, an American citizen. In the op-ed, the boy’s grandfather, Nasser al-Awlaki, described him as a “typical teenager” who watched "The Simpsons," listened to Snoop Dogg, read Harry Potter and was on his way to find his father when he was killed by a U.S. drone strike.

Speaking on a panel at the Aspen Security Forum, an annual gathering on national security issues, Johnson described his reaction to the piece.

“The point I want to make is that for any responsible official of our government involved in counterterrorism, and there are number of you in this room, you read an op-ed like that and you get a pit in your stomach, and you read it with a heavy heart,” he said. “And if you don't, you should not be involved in these decisions."

Brendan Smialowski / Getty Images Jeh Johnson, former general counsel for the Defense Department, is shown at a hearing of the Senate Armed Services hearing on Nov. 10, 2011.

The op-ed was the subject of discussion among those attending the conference, but Johnson, who oversaw legal approvals for military drone strikes at the time of the younger Al-Awlaki’s death, was the highest ranking official to speak out on the issue.

Attorney General Eric Holder, in a letter to Congress last May, acknowledged that a drone strike had inadvertently killed the younger Awlaki – one of four Americans slain in drone attacks. The only one of the four who was specifically targeted was the boy’s father, Anwar Al-Awlaki, according to Holder’s letter.

Holder identified the other two American victims as Samir Khan, who ran al Qaeda’s web-based propaganda magazine Inspire, and Jude Kenan Mohammed of Raleigh, N.C., who reportedly was killed in Pakistan in 2011.

In the op-ed, Nasser Al-Awlaki said he planned to petition a federal court to hold U.S. officials responsible for the drone strike.

“My grandson was killed by his own government,” he wrote. “The Obama administration must answer for its actions and be hold accountable.” (The Justice Department has previously asserted that the families of victims of drone strikes don’t have standing to sue in the U.S. courts and Johnson did not address that issue in his remarks. A Justice spokesman did not respond to a request for comment. )

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Another speaker on the same panel, ACLU Executive Director Anthony Romero, praised ex-National Security Agency contractor Edward Snowden, saying that “he did this country a service” by disclosing secret NSA surveillance — including the collection of millions of Americans phone records. That has given his group and others legal standing to challenge constitutionality of those programs, he said, adding, “Guess what? … I think our country is better as a result of the revelations of Mr. Snowden.”

That drew a strong reaction from other panelists, including ex- Rep. Jane Harman, who formerly served as top Democrat on the House Intelligence Committee. She called Snowden “totally self-centered and narcissistic” and said his disclosures had done damage to national security. “It's not just the information about these (NSA) programs, much of which was in the public domain: It’s a whole bunch of other stuff which compromises ongoing investigations, which I think is way off.”

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