Ambassador Ryan Crocker made it clear that diplomats who put their safety before that of the U.S. were "in the wrong line of business."
"As we try to staff the embassy in Iraq, it is good for all our colleagues to remember that we took an oath to serve our nation worldwide when we joined the foreign service, just as the military swore an oath," Crocker told reporters during a news conference in Dubai.
Crocker's comments followed a week of uproar by diplomats over the policy, including a contentious town hall meeting Wednesday where angry foreign service officers raised concern about the "" of being ordered to work in Iraq.
Asked about these concerns, the ambassador said: "You run a risk in Iraq. We try to manage and minimize the risk, but we cannot eliminate it entirely."
The State Department says three foreign service personnel - two diplomatic security agents and one political officer - have been killed in Iraq since the war began in March 2003.
The union that represents diplomats says the security situation is precarious and the completion of a new, heavily secured embassy compound and living quarters in Baghdad has been beset by logistical and construction problems.
Calling Iraq "the most important challenge," Crocker said joining the foreign service "does not mean you can choose the fight."
"It's not for us to decide if we like the policy or if the policy is rightly implemented," said Crocker. "It's for us to go and serve, not to debate the policy, not to agree with it."
Secretary of State Condoleezza Riceto all U.S. embassies and missions abroad explaining the decision to launch the largest diplomatic call-up since Vietnam, State Department spokesman Sean McCormack told reporters soon after Wednesday's meeting.
Rice was making clear in the cable that foreign service officers have an obligation to uphold the oaths they took to carry out the policies of the U.S. government and be available to serve anywhere in the world, McCormack added.
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 U.S. Embassy in Baghdad and in Iraqi provinces. Those notified have 10 days to accept or reject the offer. 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.
McCormack has said that since the call-up to fill the 48 vacant Iraq posts was announced last Friday, 15 diplomats have volunteered to work there.
"The most important service for the U.S. at the present time is in the world's hardest places," Crocker said on Friday, referring to Iraq, Pakistan and Afghanistan.
In 1969, 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.
Crocker is scheduled to travel to Istanbul, Turkey, on Friday evening for a regional conference the next day with Iraq's neighbors. He has been on a tour of Arab countries in the Mideast, trying to persuade more of them to dispatch ambassadors to Iraq.