An historic visit to the US by Vietnam's Prime Minister Phan Van Khai is a measure of how far relations have improved since the Vietnam War, the BBC's Vietnamese service reports.

When Phan Van Khai shakes hands with George W Bush in Washington on Tuesday, it will be seen in his home country as a huge boost to Vietnam's social and economic status.

Public opinion in Vietnam is overwhelmingly positive about the visit, the first by a Vietnamese leader since the end of the Vietnam War 30 years ago.

State-run media has been reporting on how important it is for Vietnam to tap into the US market, and the mood of optimism is clear from e-mails pouring in the BBC Vietnamese service, talking of a "new era" for Vietnam.

"I trust that the visit will help improve relationships with the United States in order to bring in more foreign investment and lessen China's influence in the region,' said contributor An Bang.

Dissident voices

But the visit is not without risks.

I hope that President Bush will put pressure on Prime Minister Khai to allow freedom of opinion
BBC contributor

Critics of the ruling Communist Party are hard to find inside Vietnam at any time.

But according to Professor Carl Thayer at Johns Hopkins University, "there are dissident voices within the Party who fear that this is moving too close to a country that ... is pressuring Vietnam to evolve in a line that is more towards democracy and away from socialism".

There are also concerns, among those calling for improved human rights and greater political freedom in Vietnam, that the visit and its focus on economic ties will mean their voices are no longer heard.

However, Professor Nguyen Manh Hung of George Mason University said people involved in rights work in Vietnam would welcome the visit as a chance to push for their agendas.

Readers of the BBC's Vietnamese service took a similar view.

"I hope that President Bush will put pressure on Prime Minister Khai to allow freedom of opinion and to have humane treatment to democracy advocates in Vietnam, as this is the only key to take the country forward and not lagging behind neighbouring countries," one contributor said.

The issue of political and religious freedom is regularly raised by the US with the Vietnamese government, and in 2004 the country was included on the US's list of Countries of Particular Concern.

But it is less likely to feature heavily in these talks, as in April the US acknowledged progress in some areas, including the release of several high-profile religious dissidents.

These releases were approved precisely so that the visit could take place, Professor Thayer said.

Nonetheless, observers will be studying President Bush's speeches closely for references to human rights and democracy, as well as studying Mr Khai's reactions to what is said.

Protesters

Protests against the Vietnamese government are expected, but will probably do little to disrupt the visit itself.

Professor Nguyen said such protests "lend support to those in the American leadership, especially in the Bush administration, who insist that human rights and democratisation in Vietnam remain important issues on the agenda of US-Vietnam talks".

One place where criticism is likely to be fierce is California, specifically Little Saigon, home of the overseas Vietnamese community, where the majority of people are strongly anti-communist.

Many of them are former 'boat people' who risked their lives fleeing Vietnam in the late 1970s or suffered heavily under communist rule, and they are unlikely to see Mr Khai's visit as cause for celebration.

Feelings are especially aroused after last week's news that the Malaysian government had agreed to a request from Vietnam to dismantle a recently-built memorial to the thousands of refugees who died fleeing Vietnam.

It is unlikely that the official entourage will come to this part of the US.

City officials are keen to avoid a repeat of events last year when a visit by Vietnamese dignitaries was cancelled because authorities said they could not guarantee their safety. And in 1999, thousands of protestors took to the streets after a merchant displayed a picture of the late Communist leader Ho Chi Minh in his store.

But protestors are nevertheless determined their voices are heard.

Many are expected to travel to other cities where Mr Khai is visiting. E-mail campaigns have been spreading news of demonstrations and adverts called for donations towards a $70,000 full-page open letter in the Washington Post.

Whatever the lasting effects for Vietnam's global business, Mr Khai's visit signals the start of a new era of international relations for the country. If it goes well, President Bush will make the return trip to Hanoi next year.

There can be little doubt that the image of George W Bush and Phan Van Khai standing side by side in the Rose Garden will be an enormous morale boost for the people of Vietnam.