Facebook Inc Chief Executive Mark Zuckerberg laid out a vision on Thursday of his company serving as a bulwark against rising isolationism, writing in a letter to users that the company's platform could be the "social infrastructure" for the globe.In a 5,700-word manifesto, Zuckerberg, founder of the world's largest social network, offered a philosophical sweep that was unusual for a business magnate.Zuckerberg's comments come at a time when many people and nations around the world are taking an increasingly inward view. US President Donald Trump pledged to put "America first" in his inaugural address in January. That followed Britain's decision last June to exit the European Union."Across the world there are people left behind by globalization, and movements for withdrawing from global connection," Zuckerberg wrote, without naming specific movements.The question, the 32-year-old executive said, was whether "the path ahead is to connect more or reverse course," adding that he stands for bringing people together.Quoting from a letter Lincoln wrote to Congress in the depths of the Civil War, he wrote to Facebook's 1.9 billion users: "The dogmas of the quiet past, are inadequate to the stormy present."Zuckerberg said that Facebook could move far beyond its roots as a network for friends and families to communicate, suggesting that it can play a role in five areas, all of which he referred to as "communities," ranging from strengthening traditional institutions, to providing help during and after crises, to boosting civic engagement.In comments on Facebook, some users praised Zuckerberg's note for staying positive, while others declared "globalism" dead.