IN the past two decades, talkback radio has become such a powerful political force in the US that conservative giant Rush Limbaugh is a household name in middle America. Ironically, the person to whom Rush most owes his success is Bill Clinton. Although the former Democratic president is widely remembered as a centrist, he governed as a liberal during his first two years in the White House. His arrival in Washington, DC, in 1993 coincided with Rush's skyrocketing ratings. ... Meanwhile, in Australia, Stan Zemanek burst on to the scene. Just as Limbaugh's success was attributed to Clinton and the...