* Ambassador to Yemen faces death threats
* More than 1,000 U.S. diplomats at "unaccompanied" posts
* Like troops, diplomats can face post-traumatic stress
When the Yemen-based branch of al Qaeda placed a bounty on her husband's head, Mary Feierstein learned of it from a friend who called and said, "You must be a mess!"
U.S. Ambassador Gerald Feierstein was thousands of miles (km) away at the U.S. Embassy in Sanaa, without his wife and family on what is called an "unaccompanied" posting.
He is one of more than a thousand U.S. diplomats on such tours of duty in danger spots around the world, part of a trend that is changing the definition of being a diplomat.
Over time, his wife has learned to stay calm when the phone rings unexpectedly at her home outside Washington. For nearly five years, she has not lived in the same country as her husband, a career diplomat who specializes in the Middle East and South Asia.
After militants stormed the U.S. Embassy in Yemen last September, breaking through to the inner building and ripping plaques and lettering from the walls, Feierstein called his wife to tell her he was OK.
He had also called her a few years earlier when he was based in Islamabad, Pakistan, and a bomb went off near his residence. He was unhurt in that attack.
But when Al Qaeda in the Arabian Peninsula - considered by U.S. officials to be al Qaeda's most dangerous affiliate - offered 3 kg of gold last December for the killing of Feierstein, it was Mary's turn to call her husband. He played down the danger.
"He said it was old news. They are constantly under threat, you know," Mary Feierstein said in her first media interview since the threat.
After a police officer came to her home to give her his card and tell her to call him if she needed any help, "that's when I got scared," Feierstein said.
The new perils for foreign service officers were spotlighted last Sept. 11, when militants overran the temporary U.S. mission in Benghazi, Libya, killing four Americans, including Ambassador to Libya Chris Stevens. Two other U.S. diplomats were killed in Afghanistan in the past year.
President Barack Obama, still grappling with controversy over the Benghazi attack, called on Congress on Friday to fully fund his $4 billion embassy security budget request.
In a memorial ceremony earlier this month at the State Department, Vice President Joe Biden said that diplomats "take risks that sometimes exceed those of the women and men in uniform."
Honored along with Stevens were Sean Patrick Smith, Tyrone Woods and Glen Doherty, who died in Benghazi; and foreign service officers Anne Smedinghoff and Ragaei Said Abdelfattah, killed in Afghanistan in 2013 and 2012.
FIVE-FOLD INCREASE IN UNACCOMPANIED DIPLOMATS
The State Department says there are about 1,100 U.S. foreign service officers now at posts abroad where they are unaccompanied or there are limits on who can accompany them - usually meaning no children.
That is a five-fold increase in unaccompanied American diplomats over the past decade, and represents about 14 percent of U.S. foreign service officers serving overseas.
The change began with "civilian surges" into the war zones of Iraq and Afghanistan to help with stabilization and reconstruction. Over 400 unaccompanied diplomats are in those countries.
Then, the Arab Spring uprisings starting in 2011 added many unstable countries to the list where the State Department did not want to send families.
The fluctuating list now includes Afghanistan, Iraq, Pakistan, Yemen, Libya and Tunisia, as well as the new African state of South Sudan, the State Department said.
The U.S. embassies in Algeria, Sudan and Lebanon are in the "limited accompanied" category as is the U.S. Consulate in Mexico's third-largest city, Monterrey, a focal point for drug-related violence.
The risks to diplomats are not all external. A 2007 State Department survey said 17 percent of employees who had served in dangerous posts indicated some symptoms similar to those of post-traumatic stress disorder. The department, following the military's lead, has set up a program to help diagnose and treat PTSD in its employees.
Mary Feierstein realized she was one of an expanding group of left-behind relatives when she started attending the year-end holiday parties the State Department throws for them, and noticed the crowd getting bigger every year.
She also noticed a lot of small children at those parties, and admitted to thinking, "At least my kids are grown." Her children, two daughters and a son, are all in their 20s. Her son has served two tours of duty with the Marines in Iraq.
Then-Secretary of State Hillary Clinton attended the holiday parties, at which some of the unaccompanied diplomats were Skyped in from abroad. Feierstein said she thought Obama should attend too.
The president did call Gerald Feierstein to thank him for his service after the Yemen embassy was attacked last Sept. 13, two days after the Benghazi assaults.
The United States used to be quicker to evacuate its embassies and consulates when dangers arose, said Susan Johnson, president of the American Foreign Service Association, the official union representing the Foreign Service.
These days, Washington tries to manage risks by building up the physical security of posts and increasing diplomatic security personnel, she said.
"In the process, we seem to have built a new level of tolerance for the amount of risk our diplomats face," Johnson said, adding that unaccompanied tours were increasingly becoming "a new norm."
There is pressure on diplomats to do the dangerous tours in order to advance. It is perceived to be "almost mandatory" to serve at an unaccompanied post and "punch that ticket" during a Foreign Service career, she said.
The State Department said 20 percent of its current employees had served in Iraq, Afghanistan or Pakistan.
The department offers incentives such as danger pay and shorter tours. Unaccompanied posts can be just 12 months, with several breaks, and families can often be left behind at a previous post to minimize disruption.
The State Department has made considerable progress in supporting employees in unaccompanied posts, its inspector general said in a 2010 report. Still, it said, "many returnees experience problems adjusting to their follow-on assignments," and more counseling services may be needed.
Mary Feierstein was born in Pakistan and met her husband on his first tour there in the 1970s. She said he was one of some "really tough people" that the State Department keeps cycling through stressful, dangerous posts.
Gerald Feierstein served in Lebanon unaccompanied in 2003 and 2004, then returned to Washington for a few years and was a senior official in the State Department's counterterrorism office.
He was sent to Pakistan for the third time in his career in 2008, as deputy chief of mission in Islamabad. His family stayed in the United States. In September 2010, Feierstein went to Yemen, again without his family.
"We were planning to go later. ... After the Arab Spring, we haven't been able to go there at all," Mary Feierstein said.
At home, she volunteers for the local Democratic Party and supports causes like gun control. She last saw her husband in March.
While tired of the separation, she said she felt sorrier for her children, even though they are grown. "They miss him so much. They are so happy when he comes home."