In the latest evidence of major shifts in global power dynamics, the Saudi government has approved the kingdom's partial membership in a Chinese-led economic, political and security bloc.

Saudi Arabia will join the Shanghai Cooperation Organization with the initial status of a "dialogue partner." Formed in 2001, the SCO's full members are China, Russia, India, Pakistan, Kazakhstan, Kyrgyzstan, Tajikistan and Uzbekistan.

Iran is expected to become a full member later this year, while other dialogue partners include two more countries that have traditionally been in the U.S. sphere of influence: Qatar and Egypt. Underscoring the group's security component, SCO members will conduct a joint "counter-terrorism exercise" in Russia's Chelyabinsk region -- north of Kazakhstan -- in August.

“By engaging with these U.S. rivals, it really does seem like this multipolarity is in full-bore here now,” Atlantic Council fellow Jonathan Fulton tells The Wall Street Journal.

Saudi Arabia's decision comes three months after China President Xi Jinping visited Saudi Arabia, and just days after state-owned Saudi Aramco made two world-surprising announcements signaling a huge push into China: The Saudi petrochemical giant will build a $10 billion refinery in China and acquire a 10% stake in a leading Chinese oil refinery.

China recently brokered a rapprochement between longtime Middle East rivals Saudi Arabia and Iran. The two countries announced they will restore full diplomatic ties, and the kingdom credited China for serving as a "bridge" that made it possible. Xi said the dialogue will "play a major role in strengthening regional unity and cooperation.”

Speaking of regional cooperation, Saudi Arabia is also close to restoring diplomacy with the Syrian government, which was targeted for regime change by the United States with heavy assistance from Saudi Arabia, and which is still enduring the ongoing presence of US soldiers.

These developments all point to the waning influence of the United States, and the waxing clout of China. Ominously, the SCO's growing membership rolls pave the way for the next phase of de-dollarization, a trend that threatens to obliterate a principal cornerstone of American power.

Uneasy American officials have cautioned its Middle East affiliates that some forms of cooperation with China could undermine their standing with the US...

...but these admonitions from the fading US empire ring increasingly hollow.