A sad chronicle of the government's spying on citizens exercising their First Amendment rights. In 1939, writes Davis (Spying on America, 1992) President Roosevelt pressed FBI director J. Edgar Hoover to investigate ``sabotage, espionage, and subversive activities.'' With WW II looming, he was right to fear the first two. But, Davis shows, Hoover concerned himself largely with the third sphere, compiling dossiers on millions of Americans who harbored socialist sympathies or protested the governing policies of the era. In 1956, President Eisenhower authorized increased surveillance of suspected radicals, even endorsing Hoover's program of illegal breaking and entering to photograph ``secret communist documents.'' With the rise of the antiwar movement in the 1960s, the antisubversion elements of the FBI embarked on their elaborate, and infamous, COINTELPRO operation, which extended breaking and entering to new heights: infiltrating leftist organizations with paid informants and agents provocateurs who encouraged peaceful groups to engage in terrorism; writing anonymous letters to fellow travelers, parents, and prospective employers charging leftists with illegal activities; targeting prominent dissidents with smear campaigns. The documents Davis offers are sometimes comical, as FBI agents attempt to mimic the language of hippies and Yippies and Black Panthers (``bring your own grass, pot, whatever,'' read one faked flyer announcing a demonstration). Yet, Davis shows, there was nothing at all funny about the government's secret program of violating Americans' civil rights. The COINTELPRO operation ultimately failed--thanks to federal ineptitude--and it did nothing substantial to halt the antiwar movement, which managed to stage some of the ``largest mass demonstrations ever seen in the western hemisphere'' despite the FBI's best efforts. Nelson Blackstock's Cointelpro (not reviewed) and Davis's own earlier book cover much of this ground, but this well-researched study is a welcome investigation of political corruption in the supposed service of Americanism.