Nicholson Baker likes to get to the bottom of things. His first novel, 1988’s “The Mezzanine,” followed every passing thought in the mind of a narrator riding up an escalator. He obsessed over the notion of World War II being a “good war” in 2008’s “Human Smoke”; 2001’s “Double Fold” was a fussy investigation of library preservation protocols. He once wrote a 150-page essay on the word “lumber.”

So writing “Baseless,” his book about the Freedom of Information Act, was only ever going to be an exercise in frustration. He may wish to get to the bottom of things, but FOIA, especially when it comes to matters of national security, will barely let you see where the bottom might be. Any investigative reporter will tell you that FOIA — a law enacted in 1967 that requires the federal government to release records upon request — can often obscure as much as it reveals, thanks to redactions and outright that’s-classified denials. Disappointment is constant regardless of what a journalist is fishing for, and in “Baseless,” Baker is trying to land a whopper: Did the United States use biological weapons on China and Korea during World War II and the Korean War?

The title of “Baseless” evokes Baker’s escalating anger over his lack of hard evidence to answer that question. It also points a finger at the Pentagon and the CIA for the callous human rights violations they indisputably (at least) imagined. But more directly, it refers to Project Baseless, a program launched by the Pentagon during the Korean War to study chemical and biological weapons. Its work was centered at Camp (later Fort) Detrick, a research center opened in 1942 in Frederick, Md. What did Detrick and Project Baseless do? We know some things. For instance, they explored the feasibility of dropping bombs stuffed with fleas, mosquitoes and feathers dusted with diseases that could kill crops and sicken people. We know they bred all sorts of creatures, like voles, for experiments; in 1952, hundreds of dead voles fell on parts of China, with strong circumstantial evidence that U.S. military planes had dropped them as part of biological-warfare research.

But was the vole-dropping a man-delivered plague, a decoy or something else? Amid stacks of paperwork, Baker can only speculate at the absurdity of it all. “Throwing voles from a plane is not germ warfare,” he concludes. “It’s just a stupid thing to do.”

Baker’s disillusionment is built into his book’s structure. Its chapters are diary entries written through the spring of 2019 that catalogue the scraps of knowledge he gleaned and his tussles with the FOIA infrastructure to get them. This format isn’t so much a sustained argument about America’s history of biological warfare as it is a real-life version of “Groundhog Day”; the book follows a circadian rhythm of file requests, denials, archive visits and attempts at dot-connecting, punctuated by dog walks and Baker’s puttering around his Maine home.

That structure gives the book a sweetly personal feel; no book about FOIA may be more accessible to a layperson. But it also accumulates storm clouds of despair. Baker has no firm, overarching story to tell — documents arrive “piano-rolled with redactions,” and requests are responded to with “Pleistocenian ponderousness.” All Baker can do is show you the limp pile of string he’s gathered. “Baseless” is almost inherently unsatisfying, like a memoir about a climb halfway up Mount Everest.

Still, it’s not wasted effort. Baker uncovers enough factoids — and reminds the reader of enough past U.S. military horrors — that it’s clear his hunger for clarity comes from a sensibly righteous place. The CIA, he argues, almost certainly had a hand in delivering swine fever to Cuba in 1971 and hog cholera to East Germany in 1953; it plotted and may have followed through on wrecking Guatemala’s coffee crop with invasive insects as part of its support of a 1954 coup. The military developed Operation Sphinx, a plan to drop poison gas on Japanese cities during World War II that was hidden until 1998.

And more: Detrick scientists were exploring Songo fever, a hemorrhagic fever with a death rate approaching 30 percent, in the years before an outbreak mysteriously emerged in Korea in 1951 — among American soldiers. Americans seem to often have been the unwitting test subjects and occasional victims of these misadventures. In 1950, Detrick scientists led an experiment in which the San Francisco Bay area was sprayed with organisms that simulated diseases, to see if such an airborne assault was possible. Though it was supposedly innocuous, one American died as a result. (His grandson sued the government, unsuccessfully.)

This all has left Baker furious, most pointedly at Frank Wisner, the head of covert operations at the CIA who supervised many of the outrages implemented or at least discussed during this period. But he’s also outraged at a FOIA process that slow-walks, redacts and denies responses. For the sake of efficiency and the sake of the United States being honest about itself, he makes three blunt recommendations: Double the National Archives budget, give the National Declassification Center stronger authority, and “automatically declassify any document that is more than fifty years old — no exceptions. No exceptions.”

It’s a noble desire, though one that isn’t likely to cut the way Baker plainly hopes. Even if the military’s documents were released and show what Baker suspects they do, admissions of complicity and acts of atonement would probably be absent. Document dumps from whistleblowers like Chelsea Manning and Edward Snowden have been met with concerted efforts to re-fog the contents of those records; an unchained FOIA process would be likely to leave us in the same messy, squabbling world, just with more documents in it.

But Baker is right to take on this battle as a challenge to America’s conscience in the long term. “Sometimes I don’t believe in the history of the United States,” he writes. “I don’t believe that this place deserves to have any sort of moral standing in the world. As a country. It has been the source of incalculable disruption.” Government documents will only underscore that feeling. But they can start a path toward changing it.

Baseless

My Search for Secrets in the Ruins of the Freedom of Information Act

By Nicholson Baker

Penguin Press. 450 pp. $30