In case you missed it: last week, in collaboration with Frontline, ProPublica published its must-read investigation of "Firestone, Charles Taylor, and the Tragedy of Liberia." Here's how it starts:

HARBEL, Liberia — The killers launched from the plantation under a waning moon one night in October 1992. They surged past tin-roofed villages and jungle hideouts, down macadam roads and red-clay bush trails. More and more joined their ranks until thousands of men in long, ragged columns moved toward the distant capital.

Men in camouflage mounted rusted artillery cannon in battered pickup trucks. Thin teenagers lugged rocket-propelled grenade launchers. Children carried AK-47s. Some held long machetes.

The killers wore ripped jeans and T-shirts, women’s wigs and cheap rubber sandals. Grotesque masks made them look like demons. They were electric with drugs. They clutched talismans of feather and bone to protect them from bullets. In the pre-dawn darkness, they surrounded Monrovia, the capital of Liberia.

They loosed their attack on the sleeping city. Artillery slammed into stores and homes. Mortars arced through thick, humid air that smelled of rot. Boy soldiers canoed across mangrove swamps. As they pressed in, the killers forced men, women and children from their homes. They murdered civilians and soldiers. Falling shells just missed the U.S. Embassy, hunkered on a high spot overlooking the Atlantic Ocean.

A new phase of Liberia’s civil war had begun. It would whip savagely out of control over the next decade. More than 200,000 people would die or suffer terrible injuries, most of them civilians — limbs hacked off, eyes gouged out. Half the country’s population would become refugees. Five American nuns would be slaughtered, becoming international symbols of the conflict’s depravity.

Orchestrating the anarchy was Charles Taylor, a suave egomaniac obsessed with taking over Liberia, America’s most faithful ally in Africa. For the attack that October morning, he had built his army of butchers and believers in part with the resources of one of America’s most iconic businesses: Firestone.

Read the rest here, see related videos here, and watch the full Frontline episode here.