Balko (a friend and former colleague) has documented more than 50 examples of innocent people killed in such raids. That only scratches the surface of militarization’s “collateral damage,” of course; last year, for example, “a 12‐​year‐​old Montana girl suffered severe burns after police on a drug raid tossed a flash‐​bang grenade through her window.”

“Shock and awe” tactics are fast becoming the new normal. In fact, Buffalo, N.Y., SWAT liked that moniker — first used in 2003’s invasion of Iraq — so much that it borrowed the phrase for a series of forced‐​entry drug raids three years later, oblivious to the impropriety.

For more than 25 years, federal policy has fed an unhealthy warrior mentality among what used to be called “peace officers” with subsidies and Pentagon giveaways of military ordnance.

Since 2002, the Department of Homeland Security has accelerated police paramilitarization with billions in grants feeding what Balko calls the “Police‐​Industrial Complex.” You might wonder how many police departments really need an 8‐​ton Bearcat armored personnel carrier, but “this is going to happen,” an industry spokesman brags to Balko: “We have Bearcats in 90 percent of the 100 or so largest cities in America.”

“Warrior Cop’s” horror stories are leavened by the occasional dose of dark comedy. At times, I was reminded of Mike Judge’s 2006 comic dystopia, “Idiocracy,” depicting America’s decline into a giant, dilapidated food court, its bovine population kept in line by gung‐​ho mall cops with shoulder‐​fired missiles. “Warrior Cop” features a number of stories seemingly too absurd to be true, but nonetheless amply documented.

D‐​list action star Steven Seagal has a cameo in Chapter 9, a “ride‐​along” guest when an Arizona SWAT team smashed into a private home with a tank and shot the owner’s dog (he was suspected of violating animal cruelty laws). In a wrong‐​door child‐​pornography raid in Virginia in 2006, the terrified homeowner looked up to see NBA star (and law‐​enforcement buff) Shaquille O’Neal among the semiautomatic‐​toting officers. (How often is it, exactly, that a suspected Internet creep greets the police with a hail of bullets and a cry of “You’ll never take me alive, coppers!!”?)

Another section tells the story of the Martins, a Brooklyn couple who suffered some 50 wrong‐​door raids from 2002 to 2010, ostensibly because someone at NYPD programmed their address into the computer system as a placeholder. As the examples mount, you begin to think that the least believable part of “Idiocracy” is that it’s set 500 years in the future.

Still, Balko makes a convincing case that our slide into a militarized dystopia can be reversed. First, we can stop subsidizing it. Without federal support, “we’d see more of these tactical teams disband because of the expense of maintaining them.”

Lawmakers should also mandate transparency. Dashboard cameras have exposed police abuses and exonerated wrongfully accused patrolmen. Legislation requiring helmet cameras on SWAT raids could perform a similar service. “If the drug war is being waged to protect the public, the public should be able to see exactly how the war is being waged,” Balko argues.

That’s a national conversation we actually need to have, and this indispensable book is the place to start.