Leon Panetta's first day at Pentagon helm: It's not all grim.

When Leon Panetta settles into his desk on his first day as Defense secretary Friday, he will face no shortage of challenges. There are America’s wars: the "surge" drawdown in Afghanistan, an uptick in violence in Iraq, a campaign with NATO in Libya. There is historic pressure to rein in defense spending – the Pentagon is now studying how it might cut $400 billion from its budget over the next 10 years, as part of the White House plan to reduce the nation’s long-term deficit.

There are the matters, too, of an ambitious Al Qaeda affiliate in Yemen, Iran’s nuclear aspirations, and a US relationship with North Korea that is “at the most dangerous time in quite a while,” said Sen. Joseph Lieberman (I) of Connecticut during a congressional hearing this week.

But amid these daunting pressures, some good news awaits Mr. Panetta as he takes his oath of office. Thanks in part to the work he conducted in his most recent job directing the Central Intelligence Agency (CIA), for example, Al Qaeda is in some turmoil. The trove of intelligence that Navy SEAL Team 6 recovered from Osama bin Laden’s compound in Pakistan indicates that even before the terrorist leader’s death, Al Qaeda was under “enormous strain,” as President Obama said in his June 22 troop drawdown speech.

Bin Laden had expressed concern that Al Qaeda was unable to find effective replacements for senior terrorists who have been killed, according to intelligence. Senior US officials all but heralded the group's decision to elevate to the No. 1 position bin Laden’s longtime right-hand man, Ayman al-Zawahiri, who is widely regarded among lower-ranking fighters as a prickly micromanager.

Defense analysts say the time it took to announce Mr. Zawahiri’s promotion indicates that “Al Qaeda as an organization is very nervous about communication right now,” says Brian Fishman, counterterrorism research fellow at the New America Foundation.

In its public relations efforts, Al Qaeda has indicated frustration with its inability to get much purchase around the Muslim world for its efforts to portray the United States as at war with Islam, “thereby draining more widespread support,” Mr. Obama added in his June 22 speech.

Then there's the exit timetable in Afghanistan. While senior US military officials make no secret of their concern that the 30,000 "surge" forces are being withdrawn too soon (they must be out by the end of next summer), they also acknowledge that the timeline has its benefits.

“The truth is that we would have run other kinds of risks by keeping more forces in Afghanistan longer. We would have made it easier for the [Hamid] Karzai administration to increase their dependence on us,” Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, told the Senate Armed Services Committee last week. “More force for more time is without doubt the safer course. But that does not necessarily make it the best course.”

Though the pressure is immense to cut defense spending, Panetta may be pleasantly surprised by the much greater number of resources he now has at his disposal at the Pentagon, analysts suggest. Gen. David Petraeus, commander of US forces in Afghanistan, who was confirmed Thursday as the next CIA director, has hinted he was shocked to see the difference in the two organizations’ budgets.

“I know that the [CIA] budget is classified,” Petraeus said during his June 23 confirmation hearing before the Senate Armed Services Committee, but something “came up when I was briefed on the agency budget.... Coming from the military, I kept asking, ‘Surely, there’s got to be something more you’re not telling me about?’ ”

Panetta’s former job, under the Clinton administration, as director of the White House Office of Management and Budget is widely touted as valuable experience for his new job as Defense secretary. It is heartening, say some defense analysts, that senior uniformed officials seem to value this experience, as well.

“Obviously he has a great wealth of experience,” Lt. Gen. Dennis Hejik, head of US Marine Corps Forces Command, said Thursday at the Center for Media and Security. “I think he’ll bring a lot to the Pentagon.”