Barack Obama will soon appoint a new cabinet to form the backbone of his administration in its second term. Among the most important decisions will be who replaces Hillary Clinton as US secretary of state. Over the past four years, Mrs Clinton has been an energetic steward of America’s foreign policy. She has continued her political transformation from partisan Democrat to US senator and now stateswoman who commands wide respect beyond the US. Replacing her at the state department with someone of similar gravitas is a tough call.

The president could choose a figure such as Senator John Kerry, the former Democratic presidential candidate. There are, however, indications that he may instead opt for Susan Rice, US ambassador to the UN. She has been an effective diplomat, securing UN sanctions resolutions on Iran and North Korea. Her clout was all too evident last year when she helped persuade a reluctant Mr Obama to back military action over Libya.

In recent days Ms Rice has been under steady attack from Republicans. They say that she bungled in the immediate aftermath of the Benghazi attack last September in which US ambassador Christopher Stevens died. Ms Rice argued at the time that Mr Stevens was killed in a spontaneous protest that was later hijacked by extremists, not in a premeditated terrorist assault. But this statement – based on a CIA briefing – appears to have been wrong.