Salman bin Abdulaziz, then crown prince, in January. (Uncredited/ASSOCIATED PRESS )

A 4 A.M. COMMUNIQUE from Riyadh on Wednesday detailed one of the most momentous political shake-ups in the history of Saudi Arabia. King Salman, who took office in January, in a stroke transferred power to a new generation, offered appeasement to the kingdom’s religious conservatives, reinforced his regime’s pro-American and anti-Iranian character, and underlined its intention to act boldly both at home and abroad. For the legions of analysts who have fretted that the Saudi dynasty was crumbling as its rulers aged, it was a strong corrective. But for those who have hoped to see a gradual liberalization of the Arab world’s most influential monarchy, the news was mixed at best.

U.S. officials could only be pleased that King Salman, who is 79 and in uncertain health, chose to shove aside the crown prince named by his predecessor in favor of 55-year-old Interior Minister Mohammed bin Nayef, who has worked closely with Washington on counterterrorism campaigns. Equally popular in D.C. precincts is Adel al Jubeir, 53, the U.S.-educated ambassador to Washington who was promoted to the post of foreign minister. The king meanwhile installed his favorite son, Mohammed bin Salman, as deputy crown prince, placing a prince in his early 30s in the line of succession.

These developments would be more encouraging if they were accompanied by signs the new leaders were likely to accelerate the glacial movement by the previous king, Abdullah, toward a more inclusive political system and increased civil rights, including for women. Unfortunately, the signs point to the opposite. King Salman has already taken steps to appease religious conservatives, including restoring power to the reactionary religious police. Last week’s reshuffling ousted the only female member of the cabinet, a deputy education minister.

Though admired by U.S. spies and generals, Prince Nayef has waged war against liberal reformers as well as terrorists. As Adam Coogle of Human Rights Watch put it, his interior ministry “has carried out a sweeping crackdown on peaceful dissent, using its powers to intimidate, detain, and imprison anyone who dares to criticize the government or call for serious reforms.”

The most aggressive — and reckless — actions of the Salman regime, however, have come under the command of the new heir apparent. As defense minister, Mohammed bin Salman is the face of the Saudi intervention in Yemen, a bombing campaign that so far has killed hundreds of civilians but failed to stop the advance of the Iranian-supplied Houthi forces. He can be linked, too, to a new Saudi initiative to support Syrian rebels in concert with Turkey.

Both these ventures reflect an understandable determination by the new Saudi leaders to fill what they see as the vacuum created by the Obama administration’s retreat from the Middle East. The problem is that the ambitious new missions appear poorly conceived; no one outside of Riyadh can fathom how bombing will achieve the announced aim of restoring the previous Yemeni government. The regime is drawing on its military and financial reserves at an unsustainable pace; according to a Bloomberg Business report, it spent 5 percent of the central bank’s net assets in February and March.

King Salman’s shake-up was clearly intended to entrench the kingdom’s political system for another generation. The question is whether what increasingly looks like overreaching, abroad and possibly at home, will have the opposite effect.