Trump was angry that Comey would not support his baseless claim that President Barack Obama had his campaign offices wiretapped. He was frustrated when Comey revealed in Senate testimony the breadth of the counterintelligence investigation into Russia’s effort to sway the 2016 U.S. presidential election. And he fumed that Comey was giving too much attention to the Russia probe and not enough to investigating leaks to journalists.

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In the weeks leading up to Comey’s firing, Trump administration officials had repeatedly urged the FBI to more aggressively pursue leak investigations, according to people familiar with the discussions. Administration officials sometimes sought to push the FBI to prioritize leak probes over the Russia interference case, and at other times urged the bureau to investigate disclosures of information that was not classified or highly sensitive and therefore did not constitute crimes, these people said.

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In his Tuesday letter dismissing Comey, Trump wrote: “I greatly appreciate you informing me, on three separate occasions, that I am not under investigation.” People familiar with the matter said that statement is not accurate, although they would not say how it was inaccurate.

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Within the Justice Department and the FBI, the firing of Comey has left raw anger, and some fear, according to multiple officials.  … One intelligence official who works on Russian espionage matters said they were more determined than ever to pursue such cases. Another said Comey’s firing and the subsequent comments from the White House are attacks that won’t soon be forgotten. Trump had “essentially declared war on a lot of people at the FBI,” one official said. “I think there will be a concerted effort to respond over time in kind.”

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Dating to the campaign, several men personally close to Trump deeply distrusted Comey and helped feed the candidate-turned-president’s suspicions of the FBI director, who refused to bring charges against Clinton for what they all agreed was a criminal offense, according to several people familiar with the dynamic.

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The media explosion was immediate and the political backlash was swift, with criticism pouring in not only from Democrats, but also from some Republicans. Trump and some of his advisers did not fully anticipate the ferocious reaction — …  Trump’s team did not have a full-fledged communications strategy for how to announce and then explain the decision. As Trump, who had retired to the residence to eat dinner, sat in front of a television watching cable news coverage of Comey’s firing, he noticed another flaw: Nobody was defending him.

The president was irate, according to White House officials. Trump pinned much of the blame on Spicer and Dubke’s communications operation, wondering how there could be so many press staffers yet such negative coverage on cable news — although he, Priebus and others had afforded them almost no time to prepare. 

How Trump’s anger and impatience prompted him to fire the FBI director