In 2015, Mr. Razak received an unexplained gift of $681 million from the Saudis into his personal bank account. And Mr. Mahathir’s partner in government, Anwar Ibrahim, is a strong ally of President Recep Tayyip Erdogan of Turkey, who is leading the charge against the Saudis over Mr. Khashoggi’s murder.

Several of the countries and leaders who have issued statements supporting Saudi Arabia are highly dependent on the kingdom’s aid. President Abdel Fattah el-Sisi of Egypt has extracted more than $25 billion in aid and investment commitments from Saudi Arabia and its allies since the Egyptian military toppled the popularly elected government led by the Muslim Brotherhood in 2013.

In June, after Jordan was rocked by mass protests over proposed tax increases, Saudi Arabia and two of its allies pledged $2.5 billion to prop up the Jordanian economy. And Yemen’s government is dependent on Saudi Arabia, which in March 2015 led a coalition of Sunni Arab countries in a war against the Shiite Houthi rebels who captured Yemen’s largest cities.

The Saudis use their control over the annual Hajj pilgrimage to Mecca as another means of rewarding friends and sidelining enemies in the Muslim world. Each year, the Saudi government sets quotas on the number of pilgrims from countries around the world who can receive Hajj visas, based on the percentage of Muslims in each country. The kingdom also allocates preferential blocks of Hajj visas to favored international politicians and allies.

Under King Salman and Prince Mohammed, Saudi Arabia has been quick to punish countries that cross it — or that fail to take its side in its regional conflict with Iran — by withholding aid. In early 2016, after Lebanon’s government neglected to condemn attacks on Saudi diplomatic missions in Iran, the kingdom canceled about $4 billion in aid to the Lebanese military and security forces.

In the current crisis, Prince Mohammed demanded a public expression of fealty from the Lebanese prime minister, Saad Hariri, who was detained on a visit to Riyadh last November and forced to resign in a televised speech before eventually returning to his position. Mr. Hariri had to publicly support Prince Mohammed because the kingdom remains a power broker in Lebanon and has fashioned itself the protector of the country’s Sunni community.

At this week’s economic conference in Riyadh, Prince Mohammed further humiliated Mr. Hariri, who shared the stage with him. At the end of their session, the Prince joked that Mr. Hariri would spend two days in the kingdom, adding, “I hope there are no rumors of his kidnapping.” The audience laughed and applauded obediently, while Mr. Hariri shook the prince’s hand.