After over three decades in the world of intelligence services, Michael Morell’s personal biography of his career at the CIA offers some insights about how that secretive world looks from inside. He focuses on several cases to illustrate how he evaluates successes and failures along the way. The 9/11 experience, the invasion of Iraq, Bengazi, the end of Bin Laden, and the Snowden revelations are all depicted as examples of how the CIA performed—for better (mostly) and sometimes for worse.

As the CIA and the many other intelligence agencies seek to perform their missions out of the public eye, Morell stresses that the main purpose in collecting and presenting intelligence is to offer policymakers the best analysis to make decisions. When intelligence gets too close to the policymaking process, it muddies its purpose. At the same time, he argues that intelligence agencies are subject to many layers of oversight—more than in most other countries with similar institutions. That makes life at Langley difficult to maneuver between those Congressional committees and the White House. But Morell testifies repeatedly that the Agency does its job well.

As the briefer to presidents, Morell saw the line between analysis and policymaking breached, particularly on occasion by policy officials (read VP Cheney), in the run-up to the Iraq invasion and in the hearings on the Bengazi incidents, in which four Americans were killed.

In the case of Iraq, he argues that the CIA failed in its intelligence on WMD because of something he calls analytic creep. He singled out several biases that crept into the analysts’ circles, which reflect a mix of “group think” and inadequate questioning about assumptions made in assessing Saddam Hussein’s intentions and capabilities. Those biases then became caught up in the policy debates, which led to one of the worst diplomatic blunders in U.S. history. He does not explain, however, how the checks and balances of analysts amid their conclusions can be improved to avoid another such failure. He does say that a weak link in Iraq was the lack of human intelligence on the ground, which might explain today why ISIS was not anticipated well.

In the case of the attacks in Bengazi, Morell defends not only the CIA’s assessments of how four Americans lost their lives, but also how he was personally attacked for alleged cover-up attempts in the White House. That section of the book is illustrative of clashes between intelligence agencies and policymakers, who have divergent agendas.

When it comes to the Snowden affair, Morell clearly says that Edward Snowden is a traitor, but he also raises the questions needed to determine just how so much intelligence was so vulnerable to being “pick-pocketed” so easily. He does not offer much of a recipe for avoiding that problem in the future.

One point he emphasizes in the book is that that he is not convinced that spying scandals a la Snowden have ever had long-lasting impacts on bilateral relationships. Here he is mistaken. And it is likely that, despite the main CIA mission to collect intelligence, there is a serious underestimation of what the Snowden case has done, particularly to the public realm of discussions in Germany but elsewhere, too, in the wake of the revelations of NSA activities. While much of the German debate might be posturing, there can be no doubt that the same concerns about surveillance in the U.S. so evident in the debate over the Freedom Act are present in the German parliament.

Morell has offered a strong defense of the CIA’s work. No surprise after three decades of work affiliated with it. The title of the book underscores his emphasis on the long-term need for its mission. The challenge is to secure and sustain trust in that mission among the people of the U.S. But it also requires the trust of other nations who may even depend on its capabilities. One of his chapters is called “Breach of Trust,” which focused on how Snowden was the culprit committing the breach. There is a missing chapter, however, on how the intelligence services make sure they don’t commit the same breach of trust in their work at home and abroad. Clearly the Agency needs to think about its own message when explaining itself.

The book is perhaps useful for those outside the United States seeking to understand the U.S. debate over the tools, parameters, and balance of national security policies in the coming months of the presidential campaigns—an issue that will be part of an overall discussion about future directions of U.S. foreign policy. This is as close to an inside look at a key player as we will see in public.