Since the financial crisis broke in 2008, the United Nations Security Council has looked like a poor relation to the newly empowered Group of Twenty (G-20). While world leaders tackled the crisis at biannual G-20 summits, ambassadors in New York got on with the daily grind of reviewing peace operations and routinely condemning far-flung atrocities.

The council has occasionally been in the limelight, not least during this summer's tortuous negotiations over new sanctions on Iran. But a top-level meeting on the council's role convened by Turkey this September was an illustrative bore, producing a statement calling for a "continuous process of reflection and adaptation" to make the U.N. stronger. ...