Venture capitalist and technology consultant Roger McNamee turns a hard eye on Facebook, a company in which he invested early, in "Zucked: Waking Up to the Facebook Catastrophe."

Not long before the 2016 election, writes the author, he got the sense that something wasn’t quite right with Facebook’s general run of posts. He saw “a surge…of disturbing images, shared by friends, that originated on Facebook Groups ostensibly associated with the Bernie Sanders campaign,” all of them containing “deeply misogynistic depictions of Hillary Clinton.” This flew in the face of Sanders’ conduct, as did Facebook’s allowing a slew of “inorganic” propaganda promoting such things as Brexit. All of this led McNamee to the conclusion that social media is a more effective tool for spreading messages of discord, hatred, and fear than harmony—or, as he writes, “Facebook has managed to connect 2.2 billion people and drive them apart at the same time.” His warnings to Facebook’s executives, including the fellow he calls Zuck, have gone largely ignored, while Facebook has promoted algorithms favoring big-money advertisers that rely on exploiting the private data of its users. Even given this, and even given Facebook’s “monopoly power,” few users seem quick to shed the service or to acknowledge their addiction to it. More, such internet platforms “pollute the public square by empowering negative voices at the expense of positive ones," turning the free-speech mandate of the internet’s pioneers into a forum for bullying and bullhorns. Against all this, McNamee prescribes a diet that includes not buying into the vitriol as well as erasing one’s Facebook history and not using Google because of its exploitative data-collection policies, instead using neutral search engines that do not collect data — as well as limiting one’s social media time to a few minutes a day, recognizing that these platforms are fine examples of the law of diminishing returns.

"Zucked" is a well-reasoned and well-argued case against extractive technology.

(McNamee will speak and sign copies of his book at 7 p.m. Tuesday at BookPeople, 603 N. Lamar Blvd. Information: bookpeople.com)

A poet's perspective of war

Noted poet and activist Carolyn Forché recounts an odd season at the dawn of the civil war in El Salvador in "What You Have Heard Is True."

At the opening, Forché admits she had only a little knowledge of the Central American nation of El Salvador until the end of the 1970s. “What I knew of El Salvador, I knew from my Spanish professor in college, himself a Salvadoran,” as well as from translating the work of the poet Claribel Alegría. At the beginning of the narrative, the author recounts how she opened her door one day to a man whom Alegría had mentioned without much specificity: Leonel Gómez, a mysterious figure who sometimes seemed to be all things to all people. Gómez convinced Forché that she needed to see what was happening for herself, and off she went to a nation on the brink. A bête noire soon came into view: Colonel Chacón, “who chops off fingers and has people disemboweled.” Gómez was a born mansplainer, throwing out a sequence of lessons that prompted Forché to protest that she was smart enough to follow along, to which he replied, “Lesson three has nothing to do with you.” The remark was ominous, to say the least. Gómez, her Virgil, guided Forché into tight corners, such as the cramped office of a commander who earnestly asked, “What can we do to improve the situation?” Alas, the time for talking drew short, and the bullets began to fly — some of them, it seems, deliberately aimed at her. As Forché writes in her elegiac opening, “I will learn that the human head weighs about two and a half kilos, and a child’s head, something less.” Episode by episode, dodging death squads, Forché builds a story filled with violence and intrigue worthy of Graham Greene around which a river of blood flows — doing so, unstanched, with the avid support of America’s leaders.

"What You Have Heard Is True" is a valuable firsthand report of a time of terror.