GUANTANAMO BAY U.S. NAVAL BASE, Cuba (Reuters) - Osama bin Laden’s driver knew the target of the fourth hijacked jetliner in the September 11 attacks, a prosecutor said on Tuesday.

Salim Hamdan’s lawyer said in opening statements that the Yemeni, held for nearly seven years before his trial, was just a paid employee of the fugitive al Qaeda leader, a driver in the motor pool who never joined the militant group or plotted attacks on America.

But prosecutor Timothy Stone, in an attempt to draw a link between Hamdan and the al Qaeda leadership in the first Guantanamo war crimes trial, told the six-member jury of U.S. military officers who will decide Hamdan’s guilt or innocence that Hamdan had inside knowledge of the 2001 attacks on the United States because he overheard a conversation between bin Laden and his deputy, Ayman al-Zawahiri.

“If they hadn’t shot down the fourth plane it would’ve hit the dome,” Stone, a Navy officer, said in his opening remarks.

The tribunal’s chief prosecutor, Col. Lawrence Morris, later explained that Stone was quoting Hamdan in evidence that will be presented at trial. Morris declined to say if the “dome” was a reference to the U.S. Capitol.

“Virtually no one knew the intended target, but the accused knew,” Stone said.

United Airlines Flight 93 crashed in a field in rural Pennsylvania. U.S. officials have never stated it was shot down although rumours saying that abound to this day.

Hamdan, a father of two with a fourth-grade education, is charged with conspiracy and providing material support for terrorism in the first U.S. war crimes trial since World War Two. He could face life in prison if convicted.

Prosecutors say Hamdan had access to al Qaeda’s inner circle. Stone told the jury that Hamdan earned the trust of bin Laden and helped him flee after attacks on U.S. embassies in East Africa in 1998 and the September 11 attacks.

Defendant Salim Hamdan attends his trial inside the war crimes courthouse at Camp Justice, the legal complex of the U.S. Military Commissions, at Guantanamo Bay U.S. Naval Base in this photograph of a sketch by courtroom artist Janet Hamlin, reviewed by the U.S. Military, July 22, 2008. REUTERS/Janet Hamlin/Pool

“He served as bodyguard, driver, transported and delivered weapons, ammunition and supplies to al Qaeda,” Stone said.

Hamdan was being tried in a hilltop courthouse at the U.S. Navy base in Guantanamo Bay, which has been a lightning rod for criticism of the United States since early 2002, when it began housing a prison camp to hold alleged Taliban and al Qaeda fighters from the battlefields of Afghanistan.

The war crimes tribunal system has been criticized by human rights groups and defence lawyers, some of them U.S. military officers. Detainees have been held for years without charges.

Washington has declared them unlawful enemy combatants not entitled to the rights afforded formal prisoners of war.

Responding to the widespread criticism, Morris, the chief prosecutor, said on Tuesday: “In my opinion they are seeing the most just war crimes trial that anyone has ever seen.”

WORKED FOR WAGES

Defence lawyer Harry Schneider described Hamdan as a poor Yemeni who lost his parents at a young age and lived on the streets, where he developed a knack for fixing cars.

“The evidence is that he worked for wages. He didn’t wage attacks on America,” he said. “He had a job because he had to earn a living, not because he had a jihad against America.”

“There will be no evidence that Mr. Hamdan espoused or believed or embraced any form of what you will hear about, radical Islam beliefs, extremist Muslim beliefs,” he said.

The first two prosecution witnesses were U.S. military officers who were in Afghanistan during the early days of the U.S. invasion in 2001. Both addressed a key issue at trial -- whether Hamdan had surface-to-air missiles when he was captured at a checkpoint near Takhteh Pol in November 2001.

Defence lawyers dispute the prosecution’s contention that Hamdan had the weapons. But a U.S. officer identified only as “Sergeant Major A” said the missiles were found in the “trunk of a car driven by Mr. Hamdan.”

He said troops also found a mortar manual with “al Qaeda” on the front, a book by bin Laden and a card issued to al Qaeda fighters and signed by Mullah Omar, the Taliban commander.

Ali Soufan, an al Qaeda expert with the FBI, took the jury through a long description of al Qaeda’s hierarchy and called bin Laden “the emir, the prince.” He said Hamdan was part of bin Laden’s security detail.

“The people who are around bin Laden have to be trusted ... true believers in the cause,” he said.