Tehran's nuclear activities and tanker attacks, as well as targeting of Saudi oil facility and US drone, along with Trump's pullout from nuke deal, all contributed to situation

Minority Leader Chuck Schumer details plans for 'fair and honest' trial to begin Jan. 7; Republicans pushing for swift proceedings but Trump may want longer trial to vindicate him

Former US national security adviser in a series of cryptic tweets says he was barred from his account after his September resignation, a charge Trump denies

Hawkish ex-national security adviser signs deal with Simon & Schuster; title and release date still unknown

In investigation transcripts, Vindman says there was no ambiguity; Hill says Bolton 'immediately stiffened' when EU envoy said he worked on trade for Oval Office welcome

Former US national security adviser could be a star witness for House inquiry, and would testify against strong opposition from White House

Lawyers for former national security adviser speaking to three Democratic-led House committees about potential deposition, according to US media

Taylor gives new account of quid pro quo central to impeachment probe, describing Trump's demand that 'everything' Zelenskiy wanted hinged on public vow to investigate Democrats

Former aide to fired US national security adviser said to tell lawmakers Trump's lawyer 'is going to blow everyone up' with his drive for dirt on Biden

Hawkish former national security adviser challenges centerpiece of US president's foreign policy; refuses to answer question on 'bromance diplomacy'