An ethicist for a leading conservative denomination in the United States, who was an adviser on social issues to former US president George W. Bush, says the former US practice of waterboarding terror suspects is torture and "violates everything we stand for".

Barack Obama has published secret memos detailing the legal justification for the CIA interrogation programme in the Bush era, which critics say amounted to the legitimation of torture.

The recent debate about waterboarding raises awkward questions about the religious associations of torture in US policy, says William Schweiker. He argues that it is time for repentance.