Superiors of U.S. soldier in WikiLeaks case to testify FORT MEADE, Maryland (Reuters) - The court-martial of Bradley Manning, the U.S. soldier accused of passing U.S. secrets to WikiLeaks in the biggest leak of classified information in U.S. history, continues on Wednesday, when his immediate superiors are due to take the stand. Manning, a 25-year-old private first class, is charged with providing more than 700,000 documents to WikiLeaks, an anti-secrecy website, in a case that has raised questions about the limits of secrecy and openness in the Internet era. WikiLeaks began exposing the U.S. government secrets in 2010, stunning diplomats and U.S. officials, who accused Manning of endangering lives and damaging sensitive diplomacy. In opening arguments of the trial, which began on Monday, prosecutors argued that Manning had been driven by arrogance. But lawyers for Manning, a former intelligence analyst in Iraq, portrayed him as naive but well intentioned in wanting to show the American public the reality of war in Afghanistan and Iraq. Witnesses due to testify on Wednesday are enlisted personnel who oversaw Manning. The trial is expected to run until at least late August. Reporting by Ian Simpson; Editing by Edith Honan and David Brunnstrom