The Note: Trump's credibility on the line with Comey's ouster

— -- NOTABLES

--ANALYSIS - ABC’s RICK KLEIN: In a presidency defined by the unprecedented, this is a big deal, bigger even than politics itself. These are republic-defining, Constitution-preserving stakes, courtesy of a president who has defied convention and tradition and pushed the boundaries of appropriate conduct so consistently that he has caused his motivations to be questioned even when circumstances don’t look anything like this. In this case, though, President Trump would have us believe that he decided to dismiss FBI Director James Comey organically and innocently, based on sincere outrage about the way he handled the investigation that may have handed him the presidency. Trump fired Comey in the middle of an active, sprawling investigation into his campaign’s contacts and connections with Russia, an investigation that the president himself declared to be a “total hoax” and a “taxpayer funded charade” less than 24 hours earlier. Trump and his attorney general, who was supposed to have recused himself from all matters regarding Russia and Hillary Clinton, of course celebrated Comey’s actions back when they benefited their political cause, and are now throwing Democrats’ words blasting Comey back at him. These are moments for truth and of truth for public servants, inside the Department of Justice, the Congress and even the White House, and regardless of political persuasion. Perhaps it all ends as it’s supposed to end, with a real investigation by an unimpeachable professional replacement at the FBI. Plus, Trump can’t fire Congress, at least not this easily. Trump distills almost everything to politics, the for-us-or-against-us combat in which he relishes. This now transcends that. At stake is the credibility of the federal government, period, end of story. The president doesn’t get to write the next chapter by himself.

--FBI DIRECTOR JAMES COMEY HAS BEEN FIRED: FBI Director James Comey has been fired, according to the White House. "President Donald J. Trump informed FBI Director James Comey that he has been terminated and removed from office," the White House statement reads. Comey's termination was read to him over the phone while he was traveling for the bureau in Los Angeles, two FBI sources told ABC News. A separate FBI official said that Comey first learned of his firing by seeing news reports on TV. The official said Comey was "surprised, really surprised" and was "caught flat-footed." ABC's JONATHAN KARL and MEGHAN KENEALLY have more: http://abcn.ws/2qPkZuT

--COMEY’S SUDDEN DISMISSAL LEAVES FBI’S RUSSIA INVESTIGATION IN LIMBO: President Donald Trump’s sudden dismissal of FBI Director James Comey on Tuesday came at a crucial moment in the investigation of Russian interference into the 2016 election, raising fears that the move could undermine the nearly year-long probe. “The inescapable conclusion from the circumstantial evidence here is the President wanted to stop or stifle this investigation,” Sen. Richard Blumenthal (D-Conn.) told ABC News. While the Department of Justice’s letter explaining Comey’s dismissal didn’t mention the Russia investigation, statements from the White House Tuesday made clear that the White House believes the probe has run its course. ABC’s BRIAN ROSS, MATTHEW MOSK, JAMES GORDON MEEK and RHONDA SCHWARTZ have more: http://abcn.ws/2r1bjuB

--ON GMA: SEN. TIM KAINE REACTS TO JAMES COMEY'S FIRING: Sen. Tim Kaine, the former 2016 Democratic vice presidential candidate, reacts to the timing of and reasons for Comey's firing by President Trump.“This is a firing that is an attempt to obstruct the investigation into ties between Russia and the Trump campaign and I'll tell you why I strongly believe that, there's a pattern,” Kaine told ABC’s George Stephanopoulos. WATCH: http://abcn.ws/2q1XjT2

--REACTIONS TO FBI DIRECTOR JAMES COMEY'S FIRING ARE MIXED: Following President Donald Trump's firing Tuesday of FBI Director James Comey, a number of political figures spoke out, with reactions spanning the spectrum, from approval to suspicion. ABC's RILEY BEGGIN and ADAM KELSEY take a look at the major reactions and questions raised by figures from both sides of the aisle: http://abcn.ws/2pieb9f

--COMEY GAVE INACCURATE TESTIMONY TO CONGRESS ON CLINTON EMAILS, SOURCES SAY: FBI Director James Comey gave inaccurate testimony to Congress last week regarding former Hillary Clinton aide Huma Abedin’s handling of her boss's emails, which were later discovered on a laptop belonging to Abedin's husband, Anthony Weiner, sources familiar with the investigation confirm to ABC News. Comey told the Senate Judiciary Committee on May 3 that Abedin “forwarded hundreds and thousands of emails [to Weiner], some of which contain classified information.” ABC's JONATHAN KARL and CECILIA VEGA have more: http://abcn.ws/2phpQ8h

SPEED READ with ABC’s ADAM KELSEY

TRUMP, TILLERSON TO MEET WITH RUSSIAN FOREIGN MINISTER SERGEI LAVROV. For the first time in years, Mr. Lavrov is coming to Washington -- and he's meeting with the president. The White House confirmed Tuesday night that President Trump will meet with Russia's Minister of Foreign Affairs, Sergei Lavrov, at 10:30 a.m. in the Oval Office. President Trump's only scheduled meeting on Tuesday -- the day after he fired FBI director James Comey -- will be a face-to-face with the highest-ranking Russian official he's met with so far as president, notes ABC's CONOR FINNEGAN. http://abcn.ws/2qXMAXi

SENATE REPUBLICANS DEFEND ABSENCE OF WOMEN IN HEALTH CARE WORKING GROUP. Members of the main Senate Republican group on health care legislation responded Tuesday to criticism that they are insufficiently including Republican women, but some of the least concerned members were Senate Republican women themselves, writes ABC's ALI ROGIN. While the group’s 13 senators have only met a handful of times and there are several smaller clusters of lawmakers discussing particular aspects of an Obamacare replacement, the “working group” has emerged over the past week as the most organized gathering of Republicans in the higher chamber. http://abcn.ws/2q1SUjh

US CONSIDERING SENDING UP TO 3,000 ADDITIONAL TROOPS TO AFGHANISTAN. Seeking to end a stalemate with the Taliban in Afghanistan, the Pentagon has drafted proposals for a slight increase in the number of U.S. troops in Afghanistan, as well as expanded authority to help Afghan security forces fight the group, according to a U.S. official. President Trump will have to decide on the proposals, likely before an upcoming NATO meeting. The proposals are the result of a comprehensive administration review of the U.S. strategy for Afghanistan, where the United States now has 8,400 troops, explains ABC's LUIS MARTINEZ. http://abcn.ws/2qYZBAr

SEAN SPICER DEFENDS LAG IN MICHAEL FLYNN'S DISMISSAL, TAKES AIM AT SALLY YATES. White House press secretary Sean Spicer defended President Donald Trump's handling of the dismissal of his first national security adviser, Michael Flynn. "The decision that we made was the right one. The president made a decision. He stands by it," Spicer said. This defense came amid questions over why there was an 18-day gap between the time Yates first notified the White House counsel that Flynn could have been compromised over conflicting accounts of his conversations with Russian Ambassador to the U.S. Sergey Kislyak, notes ABC's MEGHAN KENEALLY. http://abcn.ws/2qQumud

3 BIG QUESTIONS REMAIN ABOUT MICHAEL FLYNN AFTER SALLY YATES' TESTIMONY. The multi-hour Senate hearing where former Acting Attorney General Sally Yates and former Director of National Intelligence James Clapper testified Monday about the firing of former national security adviser Michael Flynn shed some light on the chain of events, but key questions remain. ABC's MEGHAN KENEALLY explains some of the biggest issues that have not been directly answered by any current or former government official. http://abcn.ws/2pxnEpg

US GAVE FRENCH 'HEADS UP' ABOUT RUSSIA'S ELECTION MEDDLING, NSA DIRECTOR SAYS. National Security Agency Director Adm. Mike Rogers said the U.S. government gave French officials “a heads up” that they observed Russian infiltration in their presidential election systems before the interference was made public, reports ABC's ALI DUKAKIS. The remark came during testimony by Rogers -– acting in his role as commander of the U.S. Cyber Command and chief of the Central Security Service -– as a witness before a Senate Armed Services Committee hearing on the posture of U.S. cyber-command on Tuesday. http://abcn.ws/2pwJOIj

WHO’S TWEETING?

@realDonaldTrump: The Democrats have said some of the worst things about James Comey, including the fact that he should be fired, but now they play so sad!

@realDonaldTrump: James Comey will be replaced by someone who will do a far better job, bringing back the spirit and prestige of the FBI.

@rickklein: Kaine: "this is a firing that is an attempt to obstruct the investigation... there's a pattern." @GMA

@JeffFlake: I've spent the last several hours trying to find an acceptable rationale for the timing of Comey's firing. I just can't do it.

@ryanstruyk: GOP reactions on Comey: McCain: "disappointed" Burr: "troubled" Corker: "raise questions" Lankford: "need clarity" Amash: "bizarre"

@PhilipRucker: Quite an exchange on Morning Joe: Sanders insisting there's "nothing there" in a Russia probes. Scarborough insisting the opposite.

@wpjenna: "Turn the lights off." Last night, Sean Spicer stood outside in the darkness and tried to explain Trump's decision: http://wapo.st/2qZiRNu