Part one of an excerpt from “The Afghanistan Papers: A Secret History of the War.” Whitlock will discuss the book during a Washington Post Live event on Aug. 31.

The suicide bomber arrived at Bagram air base in a Toyota Corolla late in the morning on Feb. 27, 2007. He maneuvered past the Afghan police at the first checkpoint and continued a quarter-mile down the road toward the main gate. There, the bomber approached a second checkpoint, this one staffed by U.S. soldiers. Amid mud puddles and a jumble of pedestrians and vehicle traffic, he triggered his vest of explosives.

The blast killed 20 Afghan laborers who came to the base that day looking for work. It also claimed the lives of two Americans and a South Korean assigned to the international military coalition: Army Pfc. Daniel Zizumbo, a 27-year-old from Chicago; Geraldine Marquez, an American contractor for Lockheed Martin who had just celebrated her 31st birthday; and Staff Sgt. Yoon Jang-ho, the first South Korean soldier to die in a foreign conflict since the Vietnam War.

Unharmed by the explosion was a VIP guest at Bagram who had been trying to keep a low profile: Vice President Dick Cheney.

Cheney had slipped into the war zone the day before on an unannounced trip to the region. Arriving on Air Force Two from Islamabad, Pakistan, he intended to spend only a few hours in Afghanistan to see President Hamid Karzai. But bad weather prevented him from reaching Kabul, so he spent the night at Bagram, an installation with personnel numbering 9,000 about 30 miles from the capital.

Within hours of the bombing, the Taliban called journalists to claim responsibility and to say Cheney was the target. U.S. military officials scoffed and accused the insurgents of spreading lies. The vice president, they said, was a mile away at the other end of the base and never in danger. They insisted the Taliban could not have planned an attack against Cheney on such short notice, especially given that his travel plans had changed at the last minute.

“The Taliban’s claims that they were going after the vice president were absurd,” Army Col. Tom Collins, a spokesman for U.S. and NATO forces, told reporters.

But the U.S. military officials were the ones hiding the truth.

In an Army oral-history interview, then-Capt. Shawn Dalrymple, a company commander with the 82nd Airborne Division who was responsible for security at Bagram, confirmed that word had leaked out about Cheney’s presence. The suicide bomber, he added, saw a convoy of vehicles coming out of the front gate and blew himself up because he mistakenly thought Cheney was a passenger.