Even after the celebrated Arab Spring, which toppled dictators and strongmen and cleared space for democracy, parts of North Africa and the Middle East remain dangerous postings for American diplomats. Sad proof came Tuesday, when an enraged mob stormed the U.S. consulate in Benghazi, Libya, killing our ambassador and three fellow Americans.

This is a time to mourn the dead, to see that the perpetrators are found and punished, and to continue working for a more peaceful, prosperous and democratic world. That goal, undoubtedly, is the reason Ambassador Christopher Stevens and his colleagues were proud to serve in a post-Moammar Gadhafi Libya that is – despite Tuesday’s outrage – finding its way back to the world.

Secretary of State Hillary Clinton vowed Wednesday that the United States “will not rest until those responsible for these attacks are found and brought to justice.” She noted that Libyan security guards tried to protect the consulate and that “This was an attack by a small and savage group – not the people or government of Libya.”

According to initial reports it was all because of an blatantly insulting anti-Islamic film, made in America, that would hardly rate a mention had it not gotten on the Internet, inciting the violence in Libya and also at the U.S. embassy in Cairo, where, fortunately, no Americans were harmed.

President Barack Obama rightly noted that “We reject all efforts to denigrate the religious beliefs of others, but there is absolutely no justification for this type of senseless violence, none.” In contrast to Obama’s words, Republican Mitt Romney gave the impression of a candidate trying to score political points in the midst of a foreign policy crisis.

It appears, from initial reports, that Ambassador Stevens and his colleagues died while trying to protect others at the consulate, a call to duty that they heard and bravely heeded.