The last time WikiLeaks made a splash was in April, when it released a trove of US government documents about prisoners at Guantanamo Bay. Today in London, Julian Assange said a financial blockade poses an existential threat to the organization, which has specialized in revealing classified information since it was launched in 2006. Today WikiLeaks suspended all publication and said it might go out of business by the end of this year. Paul Sonne reports from London for the Wall Street Journal.