BEIJING — When Turkey’s leader, Recep Tayyip Erdogan, visited Beijing this summer, he hailed a new Silk Road bridging Asia and Europe. He welcomed big Chinese investments for his beleaguered economy. He gushed about China’s sovereignty.

But Mr. Erdogan, who has stridently promoted Islamic values in his overwhelmingly Muslim country, was largely silent on the incarceration of more than one million Turkic Muslims in China’s western region of Xinjiang, and the forced assimilation of millions more. It was an about-face from a decade ago, when he said the Uighurs there suffered from, “simply put, genocide” at the hands of the Chinese government.

Like Mr. Erdogan, the world has been noticeably quiet about Xinjiang, where China has built a vast network of detention camps and systematic surveillance over the past two years in a state-led operation to convert Uighurs into loyal, secular supporters of the Communist Party. Even when diplomats have witnessed the problems firsthand and privately condemned them, they have been reluctant to go public, unable to garner broad support or unwilling to risk financial ties with China.

Backed by its diplomatic and economic might, China has largely succeeded in quashing criticism. Chinese officials have convinced countries to support Beijing publicly on the issue, most notably Muslim ones in Africa, Asia and the Middle East. They have played to the discord within the West over China. And they have waged an aggressive campaign to prevent discussion of Xinjiang at the United Nations.