THE vice president of the United States was unhappy. In 1983, a "Conservative Digest" poll of conservatives found that 64 percent of right-leaning party leaders wanted George H.W. Bush replaced on the 1984 Reagan ticket. "Light reading," Bush scribbled across a cover sheet as he sent a copy to his friend James Baker - adding a frowning face. Reagan would have none of it - he liked and appreciated Bush. But the gulf between establishment and insurgent Republicans has only grown in the ensuing decades. The elder Bush's struggles through the years with a restive right shed light on the...