NEW YORK (Reuters) - New York Mayor Michael Bloomberg on Friday opposed John Roberts' nomination to be U.S. Supreme Court chief justice, making him the first noted Republican to break with the Bush administration over who should lead America's top court. Bloomberg, a former Democrat seeking re-election in a heavily Democratic city, said Roberts had failed to show a commitment to upholding the 1973 Roe v. Wade Supreme Court decision establishing a right to abortion. "I am unconvinced that Judge Roberts accepts the landmark Roe v. Wade ruling as settled law," Bloomberg said. Roberts' answers to questions in Senate confirmation...