“Lost Memory of Skin” is a major new work by Russell Banks destined to be a canonical novel of its time. That is not to say it is without problems. It engages the reader in one long wrestling match. It is sometimes marred by condescension. But it delivers another of Mr. Banks’s wrenching, panoramic visions of American moral life, and this one very particular to the early 21st century. It tells of a plugged-in, tuned-out Internet culture “lost in the misty zone between reality and imagery, no longer able to tell the difference.” And it explores the terrible, dehumanizing consequences of choosing to live this way.