Almost no one noticed when the book was quietly released this summer. It has perhaps the most benumbing title in publishing history. Yet inside this volume of previously confidential legal opinions is the story of how the surveillance state grew into a monster.

Imagine the past five years of the Obama administration as they might have been. In this alternate universe, the national security state expanded by the Bush administration is disciplined by appropriate legal and constitutional constraints. The new president, despite technological advances that create vastly enlarged possibilities for ubiquitous surveillance, implements the basic reforms he had championed as a freshman senator from Illinois, protecting the privacy of innocent Americans without compromising the ability of law enforcement and intelligence agencies to track possible terrorists. With his support and leadership, Congress amends the Patriot Act to require that the government produce a warrant, or at least “specific and articulable facts,” establishing someone as a suspected terrorist before his or her data can be searched and seized. Foreign intelligence judges review those applications individually. Edward Snowden has a harder time leaking troves of secret data, because the data are no longer collected and shared in centrally accessible databases. The violations he does reveal involve closed chapters of U.S. history, not stains on the Obama record.

Of course, none of that happened. Although President Obama could have reined in the surveillance state, as we all know, he did not. The snowballing privacy abuses that Snowden exposed, starting with the PRISM program and culminating most recently in the disclosure of the National Security Agency’s encryption-cracking efforts, have threatened U.S. constitutional values and foreign policy interests without making us safer.

In expanding the surveillance state and the White House’s wartime authorities, Obama has continued a grand and unfortunate presidential tradition—fresh details of which have quietly come to light. They are found in a volume of 66 previously confidential legal opinions, issued between 1934 and 1976, that the Justice Department’s Office of Legal Counsel (OLC) released over the summer. Bearing a title that is wonky even by Washington standards, the book nevertheless is riveting reading, amounting to a secret history of the rise of the national security leviathan. But just as the book shows how that apparatus has been built up, it also tells a second story: of how public outrage, loud and sustained, can tear it back down.

The Office of Legal Counsel was founded in 1934 to provide legal and constitutional advice to the White House on what Homer Cummings, the attorney general at the time, called “the more troublesome questions arising in the administration of the executive branch of the Government.” It has since been staffed by some of the most influential constitutional lawyers of the twentieth century, including future Supreme Court justices Antonin Scalia and William Rehnquist. During the inherently subjective conditions of wartime, the OLC has tended to answer the president’s legal questions in a similar way: by finding justifications to expand executive power, often despite legal restrictions to the contrary. With important exceptions, the previously secret OLC memos repeatedly stress the “unique” threats posed by the current conflict, rather than bedrock values and rights.

The opinions that the OLC has released aren’t legally irresponsible; they are legally cautious, in their determination to defend the executive’s position by any means necessary. But their legal caution has led, in the aggregate, to the erosion of constitutional principles. As some OLC advisers themselves have warned, executive branch lawyers have helped to chip away at the First and Fourth Amendments, brick by brick, leading to the eventual collapse of their most basic protections.