“I didn’t care that Ronald Reagan had been elected president last November,” Bret muses in the novel. “This meant absolutely nothing to me at seventeen and politics have stayed that way for the rest of my life.” His dramatizations “The People v. O. J. Simpson” and “Impeachment” (on the Monica Lewinsky scandal) are, arguably, his best works. With “The Shards,” Murphy doesn’t have as globally significant a set of events to work with. Unlike in “The People” or “Impeachment,” the character material in “The Shards” doesn’t match the show’s alleged stakes.