We often hear that the world is getting smaller. But the environmentalist and writer Bill McKibben says the world is also getting bigger. Too big, in fact, for most of us. Last winter, McKibben ate only food grown within 60 miles of his home in Vermont. His latest book, "Wandering Home," chronicles his travels by foot from Vermont through the Adirondack mountains of New York. Through his books, articles and public appearances, McKibben has emerged as one of the most eloquent voices urging us to reconsider what he calls "the global scale of our lives." "People everywhere are excited by the treasures of the whole planet," he says in this commentary. "But we crave, too, the security of belonging in some place whose scale makes sense. Anyway, in the end, it’s only those vital local communities that can generate the music, the recipes, the solutions that are worth sharing around the world."