When President Biden is greeted by Vietnamese officials in Hanoi on Sunday, he will be celebrating the prospect of adding another friend in Asia to a coalition that his administration hopes will side with American interests rather than China’s and Russia’s. During Mr. Biden’s visit, the two nations will underscore their commitment to “increase peace, prosperity, and stability in the region,” a White House press statement said. Nguyen Phu Trong, the top Vietnamese leader, is expected to confer upon the United States an upgrade of strategic ties. The Biden administration…