The video shows a relaxed President Bill Clinton strolling along the Bridge of No Return, peering casually over the side and chatting with military personnel just yards from communist North Korea. Not visible is the high state of alert the photo-op imposed on the Secret Service. According to a new book, the agency violated both its own regulations and the terms of the Korean War cease-fire to protect the president during the tense moments of his brief appearance on the bridge.

Clinton toured the Demilitarized Zone during his 1993 visit to South Korea and ventured closer to North Korea than any president ever had. President Ronald Reagan went to the DMZ in 1983 but stayed about a half-mile from the North. Clinton estimated that he got as close as 10 feet from the dividing line between North and South and was visible to communist soldiers. “I looked at them,” the president quipped later, “and they were looking at us.” News reports put the distance between the president and North Korea at about 30 to 50 feet.

Clinton’s plan to go eyeball-to-eyeball with the communists caused high tension in the Secret Service, according to former agent Dan Emmett’s new book, “Within Arm’s Length: A Secret Service Agent’s Definitive Inside Account of Protecting the President.” Emmett writes that he ordered his team to load up on weapons, including pistols, M16 rifles and more than 1,000 rounds of ammunition. In doing so, he says, he ignored a condition of the 1953 cease-fire that prohibited rifles in the vicinity of the bridge. Emmett also told each team member to have a round in the rifle’s chamber, which he said violated a Secret Service regulation for long guns. He felt vindicated in issuing the orders when his team arrived at the bridge to find the communists armed with Kalashnikov AK-47 rifles.

“I felt the situation was serious — damned serious, in fact — and I was not risking my team or the life of the president based on a forty-year-old agreement I had correctly predicted would be broken by the Communists,” Emmett writes in the book, due out June 10.

The North Koreans stoked tensions further before Clinton’s arrival by pointing their rifle scopes toward the South Korean side — a provocative action that the Americans countered only by staring back through their binoculars. “Although our M16s were scoped,” Emmett writes, “we kept our rifles low and out of sight.”

“Within Arm's Length: A Secret Service Agent's Definitive Inside Account of Protecting the President” by Dan Emmett. (St. Martin's)

The Secret Service was reluctant to discuss Emmett’s portrayal of events. “For very obvious reasons it is inappropriate for any current or former Secret Service employee to ever discuss protective operations, condition of weapons or amount of ammunition agents carry,” Edwin M. Donovan, an agency spokesman, said in an e-mail.

The night before Clinton’s visit to the bridge, Emmett writes, the commanding officer of the nearby United Nations military post outlined what might happen if the North Koreans attacked. Chances of surviving an assault, the officer said, were low. He explained that it would take about 10 minutes for a team of shock troops to arrive to engage the North Korean forces. For any survivors, he said, “it will be the longest ten minutes of your life.” Emmett writes that his team appreciated the officer’s honesty, as well as his toast to the success of the mission and the survival of the team and the president.

When Clinton’s convoy arrived and the president emerged from his Humvee, Emmett felt a kick of adrenaline as he tightened his grip on his rifle. He had done all he could to prepare for the possibility of “unprovoked violence by the always unpredictable forces of North Korea,” he writes. “From our position we could see a noticeable increase in activity and movement from the North Korean observation post. If a gunfight were going to happen, it was going to happen within the next few seconds.”

In his memoir, “My Life,” Clinton devotes little space to his trip to the DMZ, emphasizing both how close he came to the other side and how enduring the communist threat had been. “I walked out onto the Bridge of No Return,” he writes, “stopping about ten feet from the stripe of white paint dividing the two countries and staring at the young North Korean soldier guarding his side in the last lonely outpost of the Cold War.”

Emmett was eager for the president to conclude his visit. He notes that Clinton strolled about as if walking the grounds of Camp David, going “a little farther onto the bridge than he probably should have, practically into North Korea.” Finally, to the agent’s relief, the president got back into his vehicle and, Emmett writes, “we got the hell out of the zone.”