RIO DE JANEIRO (AFP) – US President Barack Obama held up emerging powerhouse Brazil on Sunday as a model of economic and democratic transformation that leaders in the troubled Middle East should try to copy. Obama's keynote address in Rio de Janeiro was the highlight of his visit to Brazil, the first stop on a three-nation Latin America tour overshadowed by US-led military action in Libya. The speech came after France, the United States and Britain launched missile and bomb attacks on Libyan air-defense targets to prevent Moamer Kadhafi's forces from crushing a month-old uprising against his rule. Obama did...