The tiny Pacific island nation of Nauru has been unable to contact the outside world since January, when its phone system broke down. Nauru, a nation of 12,000 inhabitants, was once a source of profitable phosphate mining. After the mines shut down, the island reinvented itself as a center for offshore bankingand, financial investigators say, for money laundering. Riots broke out after January elections, when former president Rene Harris refused to cede power to the winner, Bernard Dowiyogo. Many buildings burned down, including the telephone center and the presidential palace. Naurus diplomats abroad, cut off from their government, have no idea who is now in charge.