The International Committee of the Red Cross's unwavering neutrality has been a source of both admiration and bitter controversy.
The Red Cross carries out a variety of activities in Baghdad
Its decision during World War II not to speak out publicly on the crimes being committed in German concentration camps for fear of compromising that neutrality continues to prompt passionate debate.
So it is difficult for the agency - so proud of its utter impartiality - to stomach the first suicide attack ever carried out against it, launched by those who apparently do not see it as a neutral and benevolent force.
"It's totally un-understandable," says the ICRC's Baghdad spokeswoman, Nada Doumani.
"We've been working in Iraq since 1980. People know us. They know exactly what we're doing and what we're doing it for and we are not associated with anybody in this country, with no political government, with no military. I'm shocked."
The ICRC prides itself on being the first to arrive and the last to leave.
But attacks on those working for the ICRC in recent years have already proved that the symbol of the Red Cross or the Red Crescent does not necessarily command respect or immunity.
In a shocking incident in late 1996, six Red Cross workers were shot dead by masked gunmen as they slept in a hospital in the village of Novy Attagi, just outside the Chechen capital Grozny.
The murders rocked the organisation to its core. It pulled its foreign staff out of the country and suspended all programmes which required their presence.
It also prompted a wholesale review of security arrangements for its staff. Within months, the ICRC decided for the first time to use armed guards to protect its field workers in certain situations.
Nonetheless, the improved protection did nothing to save the lives of six further volunteers five years later.
This team was travelling in two vehicles marked with the Red Cross emblem, and were on an assignment to bring assistance to the Ituri region of The Democratic Republic of Congo, when they were killed by unidentified assailants.
Since then, individual Red Cross workers have continued to be attacked and killed.
Observers note that when aid agencies move to deal with the humanitarian issues exacerbated by Western military action - as in Afghanistan and Iraq - all aid agencies, no matter what their genesis or politics, risk being viewed as part of an unwanted international presence.
In and out
The ICRC has said it will take stock of what happened on Monday before taking any major decisions about its future in the country.
But it had in the summer already started cutting down the number of foreign staff stationed in Baghdad after a Sri Lankan aid worker was shot dead.
In the wake of the attack on the UN's Baghdad headquarters in August, which left 20 dead, the agency further reduced its foreign staff to 50 - a number that has steadily decreased since.
Several other agencies also pulled out after the attack, including Oxfam.
It is widely believed that a full withdrawal of the ICRC, which has been involved in supplying hospitals with medical equipment and drugs - including the only Baghdad centre for the mentally ill, visiting those detained by the American forces and helping families trace missing relatives - would be a great loss to many ordinary Iraqis.
Workers for the Coalition Provisional Authority say they are not able to fill the void left by aid agency pull-outs.
"The aid agencies provide the people with food, medical assistance and
construction efforts. If they were to leave, these things would not then be finding their way into the community. The Coalition Military is not
structured or equipped to conduct the task," Tim Severino, an Australian working for the authority, told BBC News Online.
"Aid agencies leaving - like the UN did - also signifies to the terrorist that they are winning. They will then attempt to drive, one by one, every agency or organisation out. The result is the common people will suffer."