THE thick mangroves either side of the Dong Cung River in Vietnam’s Ca Mau peninsula make an unlikely backdrop for an American presidential campaign.

As the crucible in which Lieutenant John Kerry’s future was forged, the maze of hazardous waterways running through the Mekong Delta is already featuring in the battle for the White House.

Mr Kerry has many weaknesses as a candidate, but if he wins the Democratic nomination a Vietnam war hero will be running against a president whose own conduct during Vietnam is now being challenged. A soldier who has tasted battle will be challenging a commander-in-chief who started a contentious war in which more than 500 Americans have died.

Thirty-five years after he returned home, having been wounded three times and decorated twice, Mr Kerry still has nightmares of a conflict which defined his life.

The singular moment took place on February 28, 1969, when the 25-year-old captain of swift-boat PCF94 was given command of a risky operation to ferry troops upriver. If a film were made of the mission it would look much like Apocalypse Now.

Crews of the 50ft boats typically consisted of a college-educated captain such as Yale graduate Lieutenant Kerry, and half a dozen 19-year-olds. Lieutenant Kerry and other captains had gone to superiors to challenge tactics that presented young Americans to the waiting Vietcong as sitting ducks every day. They were told to get on with it.

The self-assured Lieutenant Kerry, who had attended Swiss boarding school while his diplomat father was posted in Europe, decided to improvise.

Instead of presenting the length of the boat’s hull to the enemy, why not narrow the target? Instead of firing and running, why not take the fight to them? The three boats transporting 30 South Vietnamese Popular Forces came under fire from the bank. “Turn 090. All boats turn 090,” Lieutenant Kerry shouted, “charge the beach”. The tactic surprised the ambushers. At least one was killed while others fled. The boats left the troops to sweep the area and headed upriver. Within 200 yards a rocket shell smashed through the portside windows of Lieutenant Kerry’s boat. Again, he ordered the boats to charge the beach.

On shore, emerging from a foxhole 10ft away, a surprised Vietcong guerrilla pointed a rocket launcher at Lieutenant Kerry’s boat. The senator wonders to this day why the guerrilla failed to fire. Possibly he thought he was too close to his target to escape shrapnel. He instead turned and ran. Lieutenant Kerry grabbed an M16, chased and killed him.

Lieutenant Kerry’s tactics broke the rules. As a captain he should not have left his boat, let alone ram it ashore. Swift-boat crews were not trained to assault the muddy land. For a start, their footwear was more akin to deck shoes than combat boots.

His commanding officer wondered whether to commend Lieutenant Kerry or court martial him, only half-joking. He wrote him up for a Silver Star. “The extraordinary daring and personal courage of Lieutenant Kerry in attacking a numerically superior force in the face of intense fire were responsible for the highly successful mission,” the citation read.

Despite endangering his crew, Lieutenant Kerry’s courage won their admiration. “He saved the day and our lives,” Fred Short, his gunner, said.

Two unscripted moments during the past month have already illustrated how Vietnam could play into the presidential election.

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