Steve Bannon, Trump’s chief strategist in the White House, is the former executive chairman of Breitbart News.
FISA is a 1978 law that created a system to hear requests to surveil foreign intelligence agents. It differs from a regular criminal warrant because it does not require the government to provide probable cause that a crime has occurred. Instead, under FISA, the government must simply provide evidence that the target of an investigation is an agent of a foreign power.
Such targetable agents would include Russian diplomats such as Sergei Kislyak, the ambassador who spoke with a number of Trump aides. But a FISA warrant could also include others for whom investigators could muster probable cause, potentially including entities directly connected to Trump.
