The House of Saud is in crisis. In the bitter struggle for the mastery of the palace in Riyadh, Crown Prince Mohammed bin Salman has made the first strike by detaining two of the kingdom’s most senior princes, Ahmed bin Abdul Aziz and Muhammad bin Nayef. In effect it is a crackdown on dissenting royals. Though a fullfledged palace coup is unlikely, no other prince, albeit lower down the pecking order, can mobilise enough troops to depose a man with the coercive powers of the state at his disposal, and still more with the octogenarian King Salman fighting age and illness.

Till Wednesday afternoon, it was rather unclear whether they have been detained for shortterm interrogation or whether they will be imprisoned. Suffice it to register that Saturday’s action was a preemptive strike to intimidate those who have dared to question his leadership style from inside the royal household. Although Mohammed is the crown prince, he plays the role of king.

He remains in control of all economic, political, social and foreign relations, and as the unofficial ruler of Saudi Arabia, he is said to have eclipsed his father. While he has apparently entrenched his position, he has made confusion over the line of succession worse confounded. The arrests were ordered after the royal court was given details of an alleged plot to undermine Prince Mohammed’s ascendance to the throne.

Among the two princes he arrested, Ahmed is the most eligible to become king. He is the only remaining brother of the incumbent King Salman and would have been first in line had his brother not promoted his own heir. In the aftermath of the detentions, there is speculation in Riyadh that the detained princes were planning to withdraw their support should Mohammed become king. In order to ascend the throne, he will seek the bayah, the oath of allegiance given by the most senior princes.

Both Ahmed bin Abzul Aziz and Muhammad bin Nayef are members of this committee, and Prince Mohammed is acutely aware that they are not overly anxious to offer their support. Though the young prince doesn’t technically need the bayahs seal of approval to become king, he will be isolated without it, and his rule will lack the legitimacy essential for a smooth succession.

As a country that derives its power from petro-dollars, it can scarcely afford the inbuilt fragility. Prince Mohammad’s idea of progress was always two-faced. While he allowed women to drive, he directed the arrest of women’s rights activists and the criminalisation of feminism. He promised religious reforms and social liberalisation while detaining hundreds of religious scholars, activists and intellectuals. He has now presided over a purge and has thus made his position decidedly untenable at the threshold.