For all the official upset over Edward Snowden's secrets, it's hard to imagine any real terrorists were shocked to learn the National Security Agency has been tracking phone conversations, emails and credit card bills.

For all the official upset over Edward Snowden's secrets, it's hard to imagine any real terrorists were shocked to learn the National Security Agency has been tracking phone conversations, emails and credit card bills.

Americans shouldn't be shocked either. The NSA's mission, budget and footprint have grown tremendously since 9/11. Its interest in data-mining has been well chronicled in books like James Bamford's "The Shadow Factory." It is an intelligence machine like the world has never known.

The NSA just opened a $1 billion data center in Utah filled with the best computers and storage units the taxpayers' money can buy. It just broke ground on a huge new computing center at its Fort Meade, Md., headquarters. What did people think they've been collecting, if not personal information about millions and millions of people?

While we're telling secrets, there's another machine the American people should know about. It is the Joint Special Operations Command, which has been waging the war on terror around the world through lethal, covert operations most voters — and even most members of Congress — know little about.

JSOC, Lt. Col John Nagl told PBS' Frontline, "is an almost industrial-scale counterterrorism killing machine."

For a decade or more, that machine has been killing people in wars everyone knows about - Iraq and Afghanistan - and in places we barely think about, like Yemen and Somalia. It doesn't fight battles or hold territory; it pursues "high value targets" put on a hit list produced through a bureaucratic process that culminates in a presidential order.

A good guide to this territory is Jeremy Scahill's recent book, "Dirty Wars: The World is a Battlefield." Like the NSA's domestic surveillance program, this is a secret that has been hiding in plain sight. Scahill does original reporting from dangerous places around the world, but much of the story is based on Congressional testimony and mainstream media reports.

JSOC, born in the ashes of the failed attempt to rescue Americans held hostage in Tehran in 1989, grew under the sponsorship of the nation's top civilian officials and military brass, including Donald Rumsfeld, Dick Cheney, Gen. David Petraeus, Gen. Stanley McChrystal and Adm. William McRaven. Its soldiers - Navy SEALs, Army Rangers and other units - come from the military branches, but JSOC operates independent of the Pentagon command structure. It's also independent of Congressional oversight. Covert actions run by the CIA must be reported to the House and Senate Intelligence committees; JSOC's covert operations don't have that requirement.

The "dirty wars" Scahill uncovers are waged by hit squads run by JSOC, the CIA — which has become increasingly militarized over the last decade — and by even more shadowy teams of Blackwater-type contractors. They operate through warlords and private militias, often, as Scahill demonstrates, picking the wrong horse to back in tribal societies like Somalia and Pakistan.

Armed drones are an important part of JSOC's arsenal, but cruise missiles, cluster bombs and armed soldiers are also used to bring the battle to high value targets — and thousands of innocents caught in the crossfire. Most Americans know this is happening — SEALs and other Special Ops warriors are celebrated in the movies as well as in newspaper accounts - but most don't know how often.

On the eve of the SEAL Team 6 mission that killed Osama bin Laden and a half-dozen members of his household in 2011, generals assured the president that that operation, if not the target, wasn't all that unusual. JSOC did 12 to 14 of those "kill/capture" raids in Afghanistan every night.

The human face Scahill spotlights in his narrative belongs to Anwar al-Awlaki. A Yemeni born and educated in the U.S., al-Awlaki earned widespread praise in the wake of 9/11 as a voice of moderate Islam. It's hard for even Scahill to say whether his harassment by the FBI uncovered al-Alwaki's radicalism or fueled his radicalization. It's also debatable whether he was placed at the top of President Obama's hit list because of al-Awlaki's effectiveness as an advocate for resistance to American foreign policy or because, as the Obama administration maintains, because he had become an operational leader of Al Qaida in the Arabian Peninsula.

Those questions might have been answered if al-Awlaki, a U.S. citizen, had been put on trial, but JSOC performs executions, not trials. A U.S. drone blew up al-Alwaki and several others riding with him in Yemen on Sept. 30, 2011. In Washington, leading figures in both parties praised the killing.

There was less praise and almost no official comment two weeks later, when al-Alwaki's 16-year-old son, Abdulrahman al-Awlaki, was killed by a drone while enjoying a picnic with his cousins. He was into hip-hop, not radical Islam, his friends said. He lived with his grandparents and hadn't seen his father in years. Born in Colorado, he was also a U.S. citizen, executed by his government.

Obama launched his career as a national politician with a speech in Chicago opposing the invasion of Iraq. He wasn't against all wars, he declared, just "dumb wars." As Scahill lays out in facts and arguments sure to make many Obama supporters, like me, uncomfortable, Obama may not have created a new kind of war, built on assassination, but he has expanded, codified and embraced it.

In a speech last month intended to open a new national debate over the war on terror, Obama acknowledged that "a perpetual war — through drones or Special Forces or troop deployments — will prove self-defeating, and alter our country in troubling ways."

But putting this genie back in the bottle, like the domestic surveillance genie revealed in the NSA leaks, won't be easy. The perpetual fear of terrorism that sprung up after 9/11 will continue to justify extraordinary measures in the name of public safety. No politician wants to be accused of letting America's guard slip. The war on terror has created huge bureaucracies like JSOC and the NSA that have powerful constituencies.

Obama's second term may be the story of two Obamas: the one who says he wants to rein in George W. Bush's Global War on Terror vs. the one waging that war on secret and not-so-secret battlefields around the world. In theory, the president ought to be able control the prying eyes of NSA snoops and reduce the size and mission of JSOC. In practice, it's not clear that he can — or that he really wants to.