Over the past few weeks, the most senior intelligence officials in the federal government have released a series of new documents which they claim shows that, starting in 2016, President Barack Obama and his deputies carried out a criminal conspiracy against President Trump. Michael S. Schmidt, an investigative reporter for The Times, explains what’s behind the sudden re-emergence on the Trump-Russia saga, and what happens when heads of the C.I.A., F.B.I. and Justice Department all turn their attention to the president’s domestic enemies.