US:Republican presidential candidates abandoned any pretence of cordiality in their second major debate as frontrunners sniped at one another and more obscure candidates burnished their conservative credentials by attacking everyone around them.
The debate, hosted by Fox News and the South Carolina Republican Party, confirmed former New York mayor Rudy Giuliani, Arizona senator John McCain and former Massachusetts governor Mitt Romney as the three men to beat, although Arkansas governor Mike Huckabee gave an eye-catching performance that could propel him out of the second tier.
Mr Giuliani recovered from an uncertain performance in the first debate, seizing every opportunity to remind voters of his primary appeal to conservatives - his record after 9/11 as a competent leader and a national security hawk.
Mr McCain rediscovered the bold, independent voice that has made him a popular figure among Democrats as well as Republicans, holding firm to his support for the Iraq war, but arguing eloquently against the use of torture.
The Arizona senator was almost alone among the 10 candidates in opposing the use of "enhanced interrogation techniques" to extract information from suspected terrorists. Mr Giuliani said that, in a hypothetical "ticking bomb" scenario, he would "tell the people who had to do the interrogation to use every method they could think of".
Mr Romney agreed, adding that the detention centre at Guantánamo Bay should be doubled in size rather than closed down.
Mr McCain, who endured torture as a prisoner of war during the Vietnam War, said that America would lose much more by torturing captives than it could ever gain in information.
"It's not about the terrorists, it's about us. It's about what kind of country we are. And a fact - the more physical pain you inflict on someone, the more they're going to tell you what they think you want to know," he said.
When Mr Romney criticised Mr McCain's support for comprehensive immigration reform, Mr McCain shot back with a reference to Mr Romney's changing positions on gay rights, abortion and gun control. "I haven't changed my position on even-numbered years or because of the different offices that I may be running for," Mr McCain said.
The most memorable exchange came when Ron Paul, a congressman from Texas, suggested that Americans should consider why they were attacked on 9/11.
"They attack us because we've been over there. What would we say here if China was doing this in our country or in the Gulf of Mexico? We would be objecting. We need to look at what we do from the perspective of what would happen if somebody else did it to us," he said.
Mr Giuliani interrupted to demand that Mr Paul should withdraw the comment, which he described as an "extraordinary" assertion. "I don't think I've ever heard that before, and I've heard some pretty absurd explanations for September 11th," the former mayor said.
Political pundits agreed yesterday that Mr Giuliani was enhanced and Mr Paul diminished by the exchange but a Fox News text message poll disagreed - putting Mr Paul ahead of all the other candidates.
