So basically, this is the crux of Thursday's testimony from former FBI Director James Comey:
1.) Based on an alarming private dinner conversation with President Trump, Comey believed that his continued employment as FBI director was contingent on showing personal loyalty to Trump. The FBI director is not supposed to be loyal to any political figure.
2.) When Trump asked Comey in a separate private conversation to "let Flynn go," Comey "took it as a direction" from the president of the United States to drop an important criminal investigation into Trump's friend and ally Michael Flynn. That is highly inappropriate and amounts to an attempt to obstruct justice.
3.) Comey did not obey the "directive" to drop the investigation into Michael Flynn. Despite repeated entreaties from the president to "lift the cloud" of the Russia investigation, that investigation also continued, much to Trump's publicly expressed frustration.
4.) Trump then fired Comey. "I was fired to change the way the Russian investigation was being conducted," Comey told the U.S. Senate, basing that conclusion in part on statements by Trump himself after the firing. Firing the head of the FBI in hopes of altering the course of an investigation is also an attempt to obstruct justice. The fact that it backfired spectacularly doesn't alter the case.
5.) Defenders of the president argue that he simply did not appreciate the gravity of what he was doing. Yet Trump clearly, carefully stage-managed these multiple conversations with Comey so that there would be no witnesses to what was being said between them, a clear indication that he did indeed understand their gravity.
6.) Comey confirmed that he told Trump on three separate occasions that Trump himself was not personally being investigated for colluding with Russia, and that the reassurances were accurate. However, the investigation into possible collusion by others in the Trump camp continues.
7.) Even before recusing himself from the Russia investigation, Attorney General Jeff Sessions was being kept in the dark about its details by the FBI because the FBI considered him possibly contaminated, for reasons that Comey said he could not discuss in open session.
8.) Trump defenders are attempting to recast the investigation with Comey as the target, as if it were a probe into whether he responded appropriately to these attempted interventions by Trump. While that's an interesting question likely to be debated by legal ethicists for years, it is nowhere near the most pressing or important question now at issue. (Interestingly, that approach assumes that Comey is indeed telling the truth about his interactions with the president.)
9.) Trump's private defense attorneys quickly issued a statement accusing Comey of lying, under oath, to Congress, which would be a felony. They claim that Trump never asked for Comey's loyalty, and never asked him to "let Flynn go." Not by happenstance, those are also the parts of the conversations that leave Trump most exposed legally.
So we're left to choose between Trump on one hand, and on the other hand a man who was testifying under oath and who has an unblemished reputation for truth-telling, recounting meetings based on memos that he wrote immediately after the conversations. According to Comey, he also told colleagues at the FBI about those conversations immediately after they occurred. At some point, special counsel Robert Mueller will want to interview those FBI colleagues about those conversations.
He will also want to interview Trump.
10.) The evidence already on the record would, in a different political environment, constitute grounds for an impeachment inquiry. That is clearly not going to happen until after the 2018 mid-terms, when the American people get their chance to return to the polls and express their sentiments about all this.