There are more questions than answers following an incident in the Gulf of Oman that could raise the stakes in a battle pitting Iran against its regional adversaries and the United States. On May 12, four oil tankers off the coast of the Emirati port of Fujairah suffered damage in what the United Arab Emirates has described as sabotage. At this point, officials have yet to provide definitive proof that foul play actually occurred. If subsequent investigation, or emerging evidence, does point to an attack of some kind, the ultimate identity of the culprits is likely to define the response to the incident....