Historians and former policymakers during the Vietnam War gathered over the weekend to analyze the origins and reasons for America's failed intervention in Southeast Asia  and whether its lessons were being applied to today's war in Iraq.  VOA's Michael Mathes attended the conference and filed this report.

Former Secretary of State Henry Kissinger (left), a key US policymaker during the Vietnam war, shares a moment with Jack Valenti, White House aide to President Lyndon Johnson

High-powered participants including former White House adviser and Secretary of State Alexander Haig, Lyndon Johnson's aide Jack Valenti, Senator Chuck Hagel and others gathered at the John F. Kennedy Presidential Library in Boston. President Jimmy Carter participated by video phone.

The program's most anticipated and controversial participant was former Secretary of State Henry Kissinger.  The 82 year-old former statesman maintained his stance that a more unified American public would have helped win the war in Vietnam.

"We have to face as a country the fact that we defeated ourselves, we weren't defeated by the Vietnamese. We defeated ourselves by the divisions," Kissinger says.

The war in Vietnam claimed the lives of  up to three million Vietnamese and 58,000 American,   and is seen by some experts as the biggest foreign policy blunder in U.S. history.

In broad-ranging discussions, Kissinger defended President Nixon's secret bombing of neighboring Cambodia during the war, and admitted that the United States would have continued the war after the Paris Peace Accords had it not been for a rapidly developing domestic crisis known as Watergate.

"I know for a fact that if it weren't for Watergate, we would have resumed bombing the Ho Chi Minh Trail in March and April 1973 when the Vietnamese were in total violation of the agreement," Kissinger says.  "They were sending 30,000 troops and hundreds of tanks and we were only waiting for the return of the last American prisoners, and if it had not been for Watergate we would have used the month of April to interrupt the supply system."

Kissinger said he had no regrets about his role in government. 

Three decades after the fall of Saigon, some of the most basic questions about the war were still being heatedly debated.

Alexander Haig, Jr., secretary of state under President Reagan, right, smiles as Henry Kissinger, secretary of state under President Ford, second from right, speaks, Saturday, March 11, 2006 during a "Vietnam and the Presidency" conference at the John F. Kennedy Presidential LIbrary and Museum in Boston. Jack Valenti, special assistant to President Johnson, third back, and Theodore Sorensen, special counsel to President Kennedy, far left, listen

Jack Valenti criticized policy-makers of the Fifties and Sixties and said their domino theory - the premise that if Vietnam fell to communism, so would the rest of Asia - was what he called a delusional, defunct mythology.

This brought a swift response from Alexander Haig.

"None of the presidents for whom I worked, ever was able to detach the cold war, the US-Soviet relationship, from the struggle in Vietnam," he says. "So whatever the historians may say about nationalism versus ideological Marxism, it's irrelevant. It's true, but it's irrelevant, because the war was dominated by the superpowers and the East-West confrontation."

Valenti, whose boss Lyndon Johnson eventually escalated the war in Vietnam by sending more than a million troops there, warned against ill-conceived military interventionism.

"That's the primary thing I learned, you cannot fight a war without public support," Valenti says.  "And the second thing is, you cannot, no matter what mighty army you are conquering a foreign land, you cannot win against an insurgency that springs from the population with their traditions and their religion and their culture. Never has been done in history."

Former President Jimmy Carter is pictured on a screen during a pre-recorded interview about issues surrounding the Vietnam War, Saturday, March 11, 2006 during a "Vietnam and the Presidency" conference at the John F. Kennedy Presidential LIbrary and Museum in Boston

The comments stirred discussion over whether the lessons of Vietnam have been heeded in the Middle East, where the US is leading a war in Iraq.

"These lessons that were learned have been largely ignored during the Iraq war,"

This is for President Jimmy Carter.   Speaking to the conference via video phone,  he said  American pre-emptive involvement in Iraq was a radical departure from previous policy.

"But it was a mistake for us to go in in effect unilaterally in a war that was not necessary, that was no threat to our national security, and pretty much based on false premises," Mr. Carter says.

Senator Chuck Hagel, a Vietnam veteran and Republican whose name has been mentioned as a possible presidential candidate in 2008,  echoed Mr. Carter's remarks, and said it was vital that a nation not commit to war unless it has a clear, definable and achievable military objective.