The US State Department is facing an unprecedented rebellion by foreign service officers over a threat to force diplomats to accept postings in Iraq, the first large-scale "directed assignments" since the Vietnam War.

Tempers boiled over at an hour-long "town hall meeting" at the department last night, where several hundred diplomats vented their anger at the decision to approve the call-up and one veteran diplomat criticised it as a "potential death sentence".

The United States is building its largest embassy anywhere on the banks of the Tigris but is still around 50 short of a target to fill 250 diplomatic posts in Iraq by next summer. It announced last Friday that it will require some diplomats - under threat of dismissal - to serve at the embassy in Baghdad or in reconstruction teams in outlying provinces.

Many at the meeting expressed serious misgivings about the ethics of sending diplomats against their will to work in a war zone, where the embassy staff is largely confined to the protected Green Zone - especially since the department is reviewing the use of private security guards.

“Incoming is coming in every day, rockets are hitting the Green Zone,” said Jack Croddy, a senior foreign service officer who once worked as a political adviser with Nato forces. He and others confronted Harry Thomas, the Foreign Service Director General, who approved the move to “directed assignments".

“It’s one thing if someone believes in what’s going on over there and volunteers, but it’s another thing to send someone over there on a forced assignment,” Mr Croddy said, to loud and sustained applause from the audience. “I’m sorry, but basically that's a potential death sentence and you know it. Who will raise our children if we are dead or seriously wounded?”

Mr Thomas responded by saying the comments were “filled with inaccuracies”.

According to the Washington Post, three State Department employees have been killed in Iraq since the US-led invasion of 2003.

The meeting became even more rancorous when John Naland, president of the American Foreign Service Association - the diplomats' union - spoke of a recent survey showing that only 12 per cent of its members believed that Condoleezza Rice, the Secretary of State, was "fighting for them".

“That’s their right, but they’re wrong,” Mr Thomas said. "Sometimes, if it’s 88 to 12, maybe the 88 percent are correct,” Mr Naland replied. “Eighty-eight percent of the country believed in slavery at one time; was that correct?” shot back Mr Thomas, who is black, in a remark that drew boos from the crowd.

Dr Rice was not present for the meeting, although her top adviser on Iraq, David Satterfield, did attend.

Sean McCormack, a State Department acknowledged the session was “pretty emotional”. He said that all diplomats sign an oath to serve, obligating them to be available to work anywhere in the world.

"It's a pretty sensitive topic and, understandably, some people are going to have some pretty strong feelings about it," Mr McCormack told reporters after the meeting.

“Ultimately, our mission in Iraq is national policy. It is the foreign policy set out by the secretary as well as the President of the United States.”

Some of those at the meeting made clear that they did not object to the idea of directed assignments. But they questioned why the State Department had been slow to respond to the medical needs of those who had served in dangerous posts.

“I would just urge you, now that we are looking at compulsory service in a war zone, that we have a moral imperative as an agency to take care of people who ... come back with war wounds,” said Rachel Schneller, who said that she had returned from a tour in Basra with post-traumatic stress disorder only to find that the department would not authorise treatment.

“I asked for treatment, and I didn’t get any of it,” she said, winning a standing ovation from her colleagues.

Under the new order, 200 to 300 diplomats have been identified as “prime candidates" to fill 48 vacancies that will open next year at the new US Embassy and in provincial postings. Those notified have ten days to accept or reject the position. If not enough say yes, some will be ordered to go.

Only those with compelling reasons, such as a medical condition or extreme personal hardship, will be exempt from disciplinary action. Diplomats forced into service in Iraq will receive the same extra hardship pay, vacation time and choice of future assignments as those who have volunteered.

More than 1,200 of the department’s 11,500 Foreign Service officers have served in Iraq since 2003. But the generous incentives have not persuaded enough diplomats to volunteer for duty there.

The last large-scale "directed assigment" was in 1969 when an entire class of entry-level diplomats was sent to Vietnam. On a smaller scale, diplomats were required to work at various embassies in West Africa in the 1970s and 1980s.

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