The shrieks echoed around Australia's boardrooms but, more pointedly, around its newsrooms. The Greens were about to take control of the Senate! The media and corporate elites circled the wagons and dragged the political elites in after them.

Just this week, the leader of the Electrical Trades Union in NSW described the Greens as ''extremist'' - one of the more polite epithets hurled at Senator Bob Brown and his colleagues since the party won almost 15 per cent of the vote at last year's federal election. Julia Gillard suggested that they did not represent ''everyday'' values, as if to imply the Greens' supporters - a significant slice of the Australian electorate - were unpatriotic.

Illustration: David Rowe

But just how ''extremist'' is the party that attracted one in six votes?

Even a casual study of its policies, and a comparison with the results of opinion polls and voter attitudes conducted over the past decade, suggests the Greens are no more radical than the centrist parties that have governed the Western world for much of the postwar period. On most issues, their values correlate with the views of a large minority of the public - well above their 15 per cent vote - and on many issues they are in tune philosophically with a large majority.