(Corrects location of nuclear plant in paragraph 27 to New South Wales state, **t Victoria state) By Matt Siegel SYDNEY, Oct 6 (Reuters) - The children of refugees who fled Leba**n's civil war for peaceful Australia in the 1970s form a majority of Australian militants fighting in the Middle East, according to about a dozen counter-terrorism officials, security experts and Muslim community members. Of the 160 or so Australian jihadists believed to be in Iraq or Syria, several are in senior leadership positions, they say. ...