Behind a quiet façade, tensions simmer. Unless the oil-producers’ cartel gets a kick from shocking the market, as it did last year, its annual meeting in Vienna today will yield few headlines. Saudi Arabia has in effect rejected calls from smaller members to reduce output (by saying non-members must cut too). Speculators are betting that prices will remain weak. The highlight will be Indonesia’s readmission, after almost seven years of absence. But with prices low, nerves are fraying. The Saudis worry that Iran, their geopolitical rival, will try to steal market share if sanctions are lifted, following July’s nuclear deal with America and others. They are concerned by rising Iraqi production, too. And their policy of driving higher-cost producers in non-OPEC America and Russia out of business has had mixed results. Saudi Arabia will probably sit tight for now. Low prices hurt, but it can bear the pain. If others can’t, too bad.