Then-National Security Adviser John Bolton speaks during a media conference in the Ukrainian capital of Kyiv on Aug. 28, 2018. Bolton, a lifelong Russia hawk, has been described as objecting to Trump’s Ukraine policy: Holding up military assistance intended to help Ukraine resist Russian military activity was antithetical to Bolton’s worldview.

Then-National Security Adviser John Bolton speaks during a media conference in the Ukrainian capital of Kyiv on Aug. 28, 2018. Bolton, a lifelong Russia hawk, has been described as objecting to Trump’s Ukraine policy: Holding up military assistance intended to help Ukraine resist Russian military activity was antithetical to Bolton’s worldview.