If somebody were to tell you that the long tragedy of human warfare entered a new and deadly phase in the fourth decade of the 20th century, the historically literate mind almost certainly would jump to the invention of the atomic bomb, which ushered in an age of anxiety and the long balance of terror between the United States and the Soviet Union.

C.J. Chivers makes a convincing case in "The Gun" that a far more lethal and consequential weapon was devised at about that same time in a sprawling Soviet military design facility — the first Avtomat (Automatic) Kalashnikov assault rifle. "The Gun" is the author's exhaustive history of the rifle's origins, development and astonishing influence on global security. The banana-clipped Kalashnikov is by now a familiar sight to anyone who watches a few minutes of television news footage; it's the weapon clasped to the chests of Kim Jong Il's goose-stepping legions, waved high by Somali pirates, clutched by Africa's wretched child soldiers, leaning up against a mud-washed wall in Osama bin Laden's infamous videos.

When contemporary American military planners talk about the new strategic challenge posed by "asymmetrical conflict," they're talking about the threat posed by irregular forces whose lethality rests in large part on AK-47s. Nuclear proliferation notwithstanding, from a security standpoint, we live not so much in the Atomic Age but in the era of the Kalashnikov.

A senior writer for the New York Times, Chivers brings experience and impressive firsthand scholarly research to bear on his subject. As a Marine Corps captain, he served in combat against the AK-equipped Iraqis in the first Gulf War, and, as a journalist, he's seen the Kalashnikov at work from Central Asia to Kurdistan to sub-Saharan Africa. Easy to produce and even easier to maintain, the weapon has been made in at least 20 factories around the world, and more than 100 million rifles now are thought to be in circulation. The truth is, he explains, that no one knows for sure. What we do know is that it has killed far more people than thermonuclear weapons, perhaps more than any other small arm, and that — because of its reliability and durability — it will go on dispensing death in every corner of the globe for generations to come.

The AK-47, Chivers points out, is the end point of a long martial quest for rapid-fire arms. It began with the wheel-mounted Gatling gun during America's Civil War and reached a kind of watershed during World War I when the collision of outmoded infantry tactics and the new heavy machine guns based on Hiram Maxim's 19th century designs turned the Western Front into an unparalleled slaughterhouse. Submachine guns were meant to put something approaching the lethality of belt-fed heavy automatic weapons into each infantryman's hands, but they were finicky and of limited utility.

German designers first came up with the idea of an "assault rifle" — one that could be fired either one shot at a time or fully automatically, thereby increasing both the range and impact of high-volume fire. In fact, Hugo Schmeisser, who, Chivers writes, designed the first working assault rifle for the Germans, worked as a prisoner of war in the same center where the AK-47 was designed and instructed his captors in the metal-stamping process that has been a key to the Kalashnikov's durability and inexpensive manufacture. (To this day, U.S. and Western military arms are machined to precise tolerances, while the AK-47 is assembled from oversized parts that are crudely stamped out.)

Chivers dwells at length on the divergence between the official Soviet history of the AK-47's design and the real story, which is equally fascinating. Soviet mythology held that the rifle was the work of an untutored genius and proletarian hero: Senior Sgt. Mikhail Timofeyevich Kalashnikov, uneducated son of the peasantry and a wounded World War II tank commander who submitted his revolutionary design to a competition and won. In fact, as Chivers writes, the AK-47 "did not result from an epiphany at the workbench of an intent Russian sergeant…. Heroism in the classic sense was nonexistent here. Spontaneity … played almost no role. The automatic Kalashnikov was the result of state process and collective work, the output not of a man but of committees." (It is a measure of Soviet perversity that their propaganda machine would attribute to heroic individual genius an achievement that, for once, vindicated Marxist dogma about the virtues of collective work and central planning.)

In any event, the achievement was real, an automatic weapon so reliable and trouble-free that its Soviet testers couldn't get it to jam, even when they soaked it in a bog and dragged it through sand. The Soviets, Chivers points out, had liberated the machine gun. They "had created the circumstances for a crossover arm, the weapon that would let automatic rifle fire jump from institutional control. The AK-47 was small … it was accurate enough … its ammunition was lightweight. Almost anyone of teenaged years or beyond could carry a few hundred rounds.… All of the things that could be done with bullets at the distances of typical small-arms engagements could now be done with one weapon that almost anyone could carry and use; the evolution of automatic arms had reached its most successful form."

What's more, even the most thick-witted or ill-educated conscript could be taught to reassemble it in a matter of minutes. The Soviets, Chivers writes, had produced an assault rifle easily used by "the small-statured, the mechanically disinclined, the dimwitted and the untrained." They had, in other words, achieved the democratization of slaughter.

The historical Kalashnikov who emerges from these pages is one of those melancholy Soviet time-servers who haunted the late 20th century like half-men or ghosts. He was actually the son of religious Kuban Cossacks, who farmed on a dusty Russian plain north of the great Kazakh steppe. His family was deported to Siberia as kulaks, and his father died of overwork there. A brother was sent to the work camps; by the end of the war, all but two of his family's men were dead. Young Mikhail struck out on his own, reinvented himself as a patriotic young Communist, served in the Red Army and then used his hearty Cossack charm to move up the ladder in the arms industry, happily taking credit for other's work as the commissars desired.

He survived on into the post-Soviet era as a lieutenant general and the public face of the Russians' export arms industry. Unlike Andrei D. Sakharov, father of the Soviet hydrogen bomb, he suffered no life-changing pangs of conscience over the influence of his "invention." Chivers quotes Kalashnikov as saying, "I sleep soundly."

So, as the result of his work, do millions of others — though not in their beds.

timothy.rutten@latimes.com