Fiona Hill and David Holmes gave powerful testimony about how everything was about to 'blow up' with Trump and Ukraine. Here are the biggest takeaways from their impeachment inquiry hearing.

• Fiona Hill, the National Security Council's former top Russia analyst, and David Holmes, a key State Department aide, were the last witnesses to testify in Congress' public impeachment hearings.
• Holmes and Hill gave riveting testimony about what they witnessed in President Donald Trump's pressure campaign to strongarm Ukraine into delivering political dirt while withholding military aid and a White House meeting.
• They forcefully defended the former US ambassador Marie Yovanovitch from the "shameful" smear campaign carried out against her by the president and his personal lawyer, Rudy Giuliani.
• The witnesses described how "shocked," "saddened," and "deeply disappointed" they were with Trump's July 25 phone call to Ukrainian President Volodymyr Zelensky.
• Hill described a stunning conversation with another US ambassador in which she told him things were going to "blow up" with Trump's Ukraine policy.
• Scroll down to read more key takeaways from Thursday's hearing.
• Visit Business Insider's homepage for more stories.

Thursday's public impeachment hearing featured the last two witnesses who testified about President Donald Trump's efforts to force Ukraine to publicly commit to investigating his political rival while withholding vital military aid and a White House meeting.

The officials who testified were:

• Fiona Hill, the National Security Council's former senior director in charge of Russian and Eurasian affairs.
• David Holmes, the counselor for political affairs at the US embassy in Ukraine.

Both witnesses laid out a devastating picture of the president and his allies' shadow foreign policy campaign in Ukraine. They described key conversations they'd had and their looming sense that things were about to "blow up."

Here are the biggest takeaways from Thursday's hearing:

• Hill said she believed testimony that Gordon Sondland, the US's ambassador to the EU, gave the previous day was "not credible."
  • Sondland was one of the "three amigos," a group of US officials who oversaw an irregular channel of US policy in Ukraine that involved pressuring the government to give Trump the investigations he wanted.
  • One of those investigations was into Burisma Holdings, the Ukrainian natural gas company that employed former Vice President Joe Biden's son, Hunter, until earlier this year.
  • Sondland testified that he didn't know at the time that when Trump said "Burisma," he really meant that he wanted an investigation into Biden, one of his main political opponents.
  • "It is not credible to me that he was oblivious," Hill said of Sondland.
  • This is indeed a dubious claim. At the time Sondland was pushing for the Burisma investigation, Trump's lawyer, Rudy Giuliani, was all over the mainstream media talking about how Ukraine should investigate the Bidens. Giuliani was also Sondland's main point of contact on the shadow Ukraine policy.
• Holmes confirmed that security assistance to Ukraine was held up for one of two reasons.
  • Either to express Trump's dissatisfaction with the fact that Ukraine had not yet publicly committed to or launched an investigation into Burisma and the Bidens, or to "increase the pressure" on Ukraine to do so.
• Hill and Holmes forcefully defended Marie Yovanovitch, the US's ambassador to Ukraine who was abruptly ousted in May after a "smear campaign" against her by Trump and Giuliani.
  • Holmes praised Yovanovitch's "dedication, determination, decency, and professionalism." He said the allegations leveled against Yovanovitch "is unlike anything I've ever seen in my professional career."
  • Hill agreed, saying the way Yovanovitch was "smeared and attacked" was "shameful."

• Both witnesses slammed the conspiracy theory promoting the idea that Ukraine interfered in the 2016 election. Hill was particularly forceful in her denunciation.
  • "I refuse to be part of an effort to legitimize an alternate narrative that the Ukrainian government is a U.S. adversary and that Ukraine-not Russia-attacked us in 2016. These fictions are harmful even if used for domestic purposes," Hill said.
  • She also singled out Republicans on the House Intelligence Committee for pushing the conspiracy, saying their actions played right into Russia's hands.
• Holmes and Hill were "shocked," "saddened," and "deeply disappointed" by Trump's July 25 phone call with Ukrainian President Volodymyr Zelensky.
  • Both officials testified about their concerns that Trump strayed from discussing US foreign policy and national security interests with Ukraine in that phone call and instead veered into domestic political territory.
  • A White House transcript of the phone call shows Trump repeatedly pressing Zelensky to "do us a favor, though," and launch the investigations the US president wanted.
  • He ordered a freeze on military aid to Ukraine days before, and testimony from a Pentagon official this week revealed that Ukrainian officials were aware of the aid being withheld the same day Trump spoke with his Ukrainian counterpart.

• "I think this is all going to blow up."
  • Hill vividly detailed a meeting with Sondland in which she learned of the divergent channels of Ukraine policy: the official channel which she and other career diplomats controlled, and the unofficial channel that involved strongarming Ukraine to accede to Trump's personal demands.
  • The former NSC analyst recalled she and Sondland had several "testy" exchanges because she was angry he wasn't "coordinating with us" on Ukraine policy.
  • She added that while she hadn't put her "finger on that at the moment," she was "irritated" with Sondland and "angry he wasn't fully coordinating."
  • "And I did say to him, 'Ambassador Sondland - Gordon - I think this is all going to blow up,'" Hill said. "And here we are."
• Hill defended Lt. Col. Alexander Vindman, the NSC's top Ukraine expert who testified in the impeachment inquiry, from racist attacks on him from the Republican party.
  • Republicans and right-wing media have repeatedly suggested that Vindman, whose family arrived in the US as refugees from Ukraine decades ago, has dual loyalty.
  • Hill denounced the attacks on Vindman as "very unfortunate."
  • "This is a country of immigrants," Hill said. "This is what, for me, really does make America great. This is, for me, this is the essence of America. It's why I wanted to be here and why I wanted to stay here."

• Thursday's witnesses gave a master class on what it means to be nonpartisan fact witnesses.
  • Hill, in particular, was a straight shooter.
  • She expressed her support for the president. She denounced the attacks on him during the 2016 campaign and after as "unfair." She said a Politico story describing Ukrainian officials' support for Hillary Clinton during the election was credible.
  • Hill sympathized with Republican lawmakers and expressed support for some of them.
  • At the same time, the former NSC official made it a point to delineate the unusual and dangerous nature of a pressure campaign against Ukraine based on political reasons. She shot down the notion that Russian interference in 2016 is a "hoax."
  • She made a powerful statement denouncing any president asking a foreign power to investigate a political rival. She forcefully defended a US ambassador from the president and his lawyer.
  • She laid out, in dramatic detail, how the president deployed his men to force a weaker ally into caving to his demands while withholding vital aid and a White House meeting.
  • Through it all, she emphasized that she and Holmes testified as "fact witnesses" and nothing more.

• Read more of Insider's impeachment coverage:
• Here's who's scheduled to testify in this week's impeachment inquiry hearings
• Think Trump will get impeached? Gambling sites say the odds are in your favor
• Trump could be impeached and removed from office but still win reelection in 2020
• Over half of the House of Representatives support the impeachment inquiry against Trump - see all of them here
• Everything you need to know about Trump's impeachment process: What's happened, who the players are, and what comes next

NOW WATCH: This top economist has a radical plan to change the way Americans vote - weighted voting