A Cambridge professor with deep ties to American and British intelligence has been outed as an agent who snooped on the Trump presidential campaign for the FBI. Multiple media outlets have named Stefan Halper, 73, as the secret informant who met with Trump campaign advisers Carter Page and George Papadopoulos starting in the summer of 2016. The American-born academic previously served in the Nixon, Ford and Reagan administrations. The revelation, stemming from recent reports in which FBI sources admitted sending an agent to snoop on the Trump camp, heightens suspicions that the FBI was seeking to entrap Trump campaign aides....