WASHINGTON — John Christopher Stevens, the American ambassador killed Tuesday in an attack in Benghazi, Libya, was a career diplomat who had served in US missions throughout the Middle East and whose last mission was focused on supporting a democratic transition in the country.
Mr. Stevens, 52, an Arabic speaker and longtime Middle East specialist, had served in Jerusalem, Cairo, and Saudi Arabia. He also worked in several jobs involving US policy in Washington. He was well-known at the State Department and on Capitol Hill, where he worked briefly for the Senate Foreign Relations Committee.
‘‘It’s especially tragic that Chris Stevens died in Benghazi because it is a city that he helped to save,’’ President Obama said.
With Secretary of State Hillary Rodham Clinton alongside him, Obama praised Mr. Stevens’s work as the envoy to the Libyan rebels last year.
‘‘He worked tirelessly to support this young democracy. And I think both Secretary Clinton and I have relied deeply on his knowledge of the situation on the ground there,’’ Obama said. ‘‘He was a role model to all who worked with him and to the young diplomats who aspire to walk in his footsteps.’’
Obama and Clinton met privately with State Department employees later Wednesday. The attack also killed diplomat Sean Smith and two others, whose identities have not been released pending notification of their families.
On Wednesday, friends and colleagues remembered Mr. Stevens as smiling, easygoing, and friendly.
Arash Babaoff, a friend of Mr. Stevens’s since the 1990s, described him as passionately committed to his work as a diplomat. ‘‘It was his life,’’ Babaoff said. ‘‘He was just someone who really had his heart in this, and he really felt like he was making relationships and headway.’’
Babaoff called the killing ‘‘a blow to idealism today.’’
Friends said Mr. Stevens also had a wry sense of humor and a direct style of speaking that is unusual for many diplomats. Preparing then-Secretary of State Condoleezza Rice for a meeting with Libyan leader Moammar Khadafy, he alluded to Khadafy’s crush on Rice.
‘‘A self-styled intellectual and philosopher, he has been eagerly anticipating for several years the opportunity to share with you his views on global affairs,’’ Stevens wrote in an August 2008 diplomatic cable published by WikiLeaks.
Rice herself later recalled Khadafy’s interest in her as ‘‘creepy.’’
Wayne White, a former Middle East intelligence official at the State Department, recalled Mr. Stevens would arrive in his office with a ‘‘big smile’’ and assign work to him.
The work might not have always been welcome, ‘‘but it was better if it came from Chris. He was just such a genuinely intelligent, high-minded guy,’’ White said.
Mr. Stevens was a native of Northern California and before entering the diplomatic corps had served as an international trade lawyer, according to the State Department. In the early 1980s, he taught English as a Peace Corps volunteer in Morocco.
The Libya posting had marked a high honor for Mr. Stevens. He had served as the number two diplomat at the US Embassy in Tripoli from 2007 to 2009.
He later served as the US envoy to the Transitional National Council, the umbrella resistance group that opposed Khadafy last year.
In a State Department briefing last year, Mr. Stevens described arriving in Benghazi in April 2011, when the city was in rebel hands but the war was not over. His mission was to set up a US diplomatic mission in Benghazi, a strong show of support for the rebel forces.
‘‘There weren’t any flights, so we came in by a Greek cargo ship,’’ Mr. Stevens said. Libyans greeted the small American group with US, British, French, and Qatari flags in the courthouse square.
In January, he was nominated for the top job in Libya.
Speaking with a Washington Post reporter in June, Mr. Stevens acknowledged a rise in violence, especially among small Islamist groups in Libya.
‘‘It’s a function of there being a lot of freedom and desire to express views and agendas. When people cross the line it’s also a function of a lack of strong state and police to enforce the law,’’ Mr. Stevens said at the time.
Mr. Stevens described himself on the Embassy’s website as ‘‘fortunate’’ to have the posting.
He appears in a State Department video with Arabic subtitles that was intended to introduce Mr. Stevens to Libyans. He enthusiastically describes his affection for the Middle East and his eagerness to expand trade, cultural, and other ties between the United States and Libya.