Ten members of the G20 have joined the United States in accusing the Syrian government of carrying out a chemical weapons attack on civilians last month and called for a strong international response.A joint statement by the 10 countries and the United States stopped short of explicitly calling for military action against the regime of Syrian president Bashar Assad, as Barack Obama is advocating.But the tough language aligned half of the G20 members with the US president, who worked the sidelines of the summit in St Petersburg to build international support for a limited US military response. The 10 countries...