Why is President Joe Biden going to Saudi Arabia next month? During his presidential campaign and for most of his first year in office, Biden treated the kingdom’s imperious and murderous Crown Prince Mohammed bin Salman as a pariah. But that was when the price of gasoline was around $2 a gallon. And it was also at a time when the murder and decapitation of journalist Jamal Khashoggi, at the crown prince’s direction, plus a ruinous Saudi-led war in Yemen, were big problems for the oil kingdom. Now, however, the calculation is different. With U.S. gasoline prices rising well above...