To mark its 40th anniversary The World Tonight has delved through the archives for key on-air moments. This ones goes back to May 1974 and the height of the Watergate Crisis which led up to the resignation of US President Richard Nixon.
One of the key moments was the publication of the transcripts of Nixon's conversations in the White House - the Watergate Tapes. On the 10th May, presenter Douglas Stuart spoke to President Nixon's special assistant, John Mclaughlan.
He started by asking him if the tapes made the president's impeachment inevitable.
The World Tonight is broadcast on Radio 4 at 2200 GMT, Monday to Friday.