Impeachment mania has gone from zero to 60 in record time in Washington. Little more than a week ago, President Trump seemed to have beaten back Democratic efforts to use the Trump-Russia affair to remove him from office. Now, he faces ferocious Democratic efforts to use the Trump-Ukraine affair to remove him from office.

But facts matter, even in an impeachment frenzy. And what is remarkable is how quickly House Democrats jumped on the impeachment train before knowing some of the basic facts of the Ukraine matter. Speaker Nancy Pelosi announced an impeachment inquiry before the rough transcript of Trump's July 25 phone conversation with Ukrainian President Volodymyr Zelensky was even released and also before an intelligence community whistleblower's complaint — the document that sparked the entire controversy — was given to Congress or the public. When those documents came out, of course, both sides claimed support for their case.

Now, there is much more to be learned and issues to be resolved as Democrats go forward with their drive to bring Trump down. Here are eight keys to the future fight:

1. The 'cover-up' and the super-secret filing system

"This is a cover-up," Pelosi declared Thursday. The speaker based her charge on information that had been quickly provided by the White House — the record of the Trump-Zelensky call, the whistleblower complaint, a Justice Department opinion, and related correspondence — but Democrats nevertheless maintained that the administration was engaged in covering up what had happened. The charge was quickly echoed in the press; the New York Times ran a giant headline, "COMPLAINT ASSERTS A WHITE HOUSE COVER-UP," while the Washington Post ran a giant headline, "Trump, GOP hit back as coverup is alleged," and the Wall Street Journal ran a giant headline, "Whistleblower Alleges Coverup."

The main basis for the cover-up charge is the whistleblower's contention that the White House took extraordinary steps to restrict access to records of the Trump-Zelensky call. "White House officials told me that they were 'directed' by White House lawyers to remove the electronic transcript from the computer system in which such transcripts are typically stored for coordination, finalization, and distribution to Cabinet-level officials," the whistleblower wrote. "Instead, the transcript was loaded into a separate electronic system that is otherwise used to store and handle classified information of an especially sensitive nature. One White House official described this act as an abuse of this electronic system because the call did not contain anything remotely sensitive from a national security perspective."

In response, the White House told CNN Friday that, "National Security Council lawyers directed that the classified document be handled appropriately."

"Appropriately" will be critical to the issue. It is well known that the Trump White House instituted tight restrictions on the distribution of presidential call transcripts after two incidents in 2017 in which transcripts of two Trump conversations, one with the prime minister of Australia and the other with the president of Mexico, were leaked to the press. The unprecedented leaks appalled national security experts, and it was entirely reasonable that the White House would tighten controls over access to transcripts. Documents that used to be shared among dozens or even hundreds of people in the executive branch were, after the leaks, shared with a much smaller number officials, often in the form of paper copies that had to be returned once read.

An additional question is what kinds of documents were stored in each system, if, in fact, the dual system described by the whistleblower exists. Were routine presidential communications kept in a more open system while super-secret presidential communications were kept somewhere else? What specific documents were in each? Would a record of the Trump-Zelensky talk be out of place in the super-secret system, absent a White House desire to cover up what Trump said, or was it normal for a presidential conversation with another head of state to be there? At the moment there are no clear answers to any of those questions. But those answers will be extremely important to the impeachment debate; in a private conversation Thursday, one Republican lawmaker said it would be remarkable for the House to impeach the president for, in essence, putting something in the wrong file cabinet.

2. What was said

Before the White House released the contents of the Trump-Zelensky conversation, government officials and commentators alike referred to it as a "transcript." But it was not a transcript. It was, rather, a memorandum of the conversation, compiled from notes taken by National Security Council staff who listened to the call as it happened. The memorandum presented Trump's and Zelensky's words as if it were a transcript but with the note that it was not an actual verbatim record of what took place. Thus, the press began referring to what was released as a "rough transcript."

Some questioned whether Trump doctored the document. "Given what we know about how Trump pressures and manipulates civil servants to tow his line, I'm not *quite* sure we can trust the transcript itself as being accurate/comprehensive," tweeted MSNBC's Chris Hayes Tuesday. Others echoed that suspicion.

If Democrats go forward with impeachment, both sides will want to know more about what the two presidents actually said to each other. That would mean looking for an audio recording of the talk — it does not appear there is one, at least on the U.S. side — and also reviewing the raw notes of the White House and perhaps other staffers who listened in. The idea would be both to get a more complete version of what was said and to dispel accusations that Trump somehow manipulated the record.

3. A William Barr recusal?

Democrats have already begun demanding that Attorney General William Barr recuse himself from the Ukraine affair. From a Democratic perspective, that was, after all, a very effective move with then-Attorney General Jeff Sessions in the Russia matter. Now, House Judiciary CommitteeCchairman Jerrold Nadler, among others, says that because the whistleblower complaint, and the president himself in the phone call, mentioned Barr's name, then the attorney general should recuse. "The President dragged the Attorney General into this mess," Nadler tweeted Wednesday. "At a minimum, AG Barr must recuse himself until we get to the bottom of this matter."

The president went ballistic, and stayed that way, when Sessions recused himself. Now, the current attorney general shows no signs that he would even consider Nadler's demand. On Wednesday, a Justice Department spokesman released a statement saying Barr has had no role in the affair. "The Attorney General was first notified of the President's conversation with Ukrainian President Zelensky several weeks after the call took place, when the Department of Justice learned of a potential referral," the statement said. "The President has not spoken with the Attorney General about having Ukraine investigate anything relating to former Vice President Biden or his son. The President has not asked the Attorney General to contact Ukraine — on this or any other matter. The Attorney General has not communicated with Ukraine — on this or any other subject. Nor has the Attorney General discussed this matter, or anything relating to Ukraine, with Rudy Giuliani." The short version of that appears to be: Sorry, Rep. Nader, but there is no way in hell the attorney general will recuse himself.

4. The House non-vote on impeachment

On Tuesday, Pelosi made an "address to the nation" on the Ukraine matter. "Today, I'm announcing the House of Representatives is moving forward with an official impeachment inquiry," the speaker said, adding that she has directed six House committees to go forward with investigations under the "umbrella" of the just-announced inquiry.

Nowhere in Pelosi's remarks was any indication that she would have the House vote to begin a formal inquiry. That was a break from past presidential impeachments. On Oct. 9, 1998, the House voted 258 to 176 to begin a "broad, open-ended impeachment inquiry," in the words of a New York Times headline. The vote forced lawmakers to make a big decision, even though it was only to start an inquiry, and not to approve any particular articles of impeachment.

Now, there's been no vote. That might become a problem in coming days when the House seeks to enforce subpoenas in the impeachment investigation. If lawmakers seek to get grand jury information, or to pierce executive privilege, they will be in a stronger position if they are conducting what courts recognize as a "judicial proceeding" — in this case, an impeachment inquiry. But it's not clear whether judges will recognize Pelosi's because-I-say-so inquiry as having the same standing as an inquiry voted on by the entire House.

5. Ukraine only?

Pelosi is said to favor a narrowly focused impeachment based entirely on the Ukraine matter. That would certainly be easier for the House to do quickly, plus it would emphasize the issue that has united the vast majority of House Democrats in favor of impeachment. The problem is, it would ignore the other issues — Russia, emoluments, campaign finance — that Democrats have highlighted in recent months and years. Indeed, Pelosi has authorized the six committees to go forward with inquiries, even though they're not all looking into Ukraine.

So there is a question whether those committee chairs will be happy to see their impeachment work end up on the cutting room floor as Pelosi and her new favorite chairman, Rep. Adam Schiff of the House Intelligence Committee, move forward with a Ukraine-only impeachment. Nor is it clear whether the Democratic base, which has faced a wrenching emotional adjustment after the failure of the Russia effort, will be satisfied with a singular focus on Ukraine. On the other hand, adding additional areas, and additional articles of impeachment, will slow down what Pelosi wants to be a quick process. At the moment, it is unclear what Democrats will do.

6. The White House witnesses

The Trump-Zelensky phone call was not a simple one-on-one conversation between two leaders. Such conversations never are. In fact, there were many people in the White House listening to the call and making notes of what the two men said. The whistleblower wrote, "Based on my understanding, there were approximately a dozen White House officials who listened to the call — a mixture of policy officials and duty officers in the White House Situation Room, as is customary." The whistleblower said State Department official T. Ulrich Brechbuhl also listened, but CBS later reported that Brechbuhl was not, in fact, on the call.

However many there were, impeachment investigators will want to interview everyone who heard the call. "We intend to follow the facts where they lead us, and that also means trying to interview the folks that were detailed in the complaint," said Democratic Representative Denny Heck, a member of the Intelligence Committee, on MSNBC Thursday night.

Whether they will able to do so is another matter. There will undoubtedly be privilege claims and other objections that might end up in court. And the resolution of those cases could hinge on the issue discussed above, whether courts will accept Pelosi's simple declaration of an impeachment inquiry as proof that the House is formally involved in a judicial proceeding. In the end, it is not clear whether House Democrats will be able to hear from everyone involved.

7. The whistleblower

There have been thousands of references to the "whistleblower" in the past few days. Some news accounts have reported a few things about his identity, most importantly that he is a CIA employee who has been detailed to the White House in the past. But the whistleblower's identity remains a secret.

That seems unlikely to last. Even a cursory glance at the whistleblower complaint suggests that the whistleblower and his legal team (and, possibly, Democrats on Capitol Hill) carefully planned the complaint campaign. As Washington veterans, they knew, or should have known, that it will be hard for the whistleblower to remain anonymous if a presidential impeachment proceeds based on the whistleblower's account.

One reason the president's defender's would like to know the whistleblower's identity — and some on the Hill believe they already know — is to examine the question of bias. The intelligence community inspector general, while determining the complaint to be "urgent" and "credible," also noted the presence of "some indicia of an arguable political bias on the part of the complainant in favor of a rival political candidate." Republicans will certainly want to look into that. Democrats will dismiss any such claims, saying it doesn't matter what the whistleblower's political convictions are if the information is accurate. But in a full-blown impeachment battle, the whistleblower's politics will almost certainly become part of the fight.

8. What the Bidens did

In the days since the Ukraine story broke, it has become common to hear Democrats and their allies in the press declare definitively that there is "absolutely no evidence" that either Joe Biden or his son Hunter did anything wrong in Ukraine. The implication is that there has been investigation upon investigation, and none found anything amiss in the Bidens' actions.

Those claims will have to be examined more closely in an impeachment proceeding. After all, if Trump was pointing to a real question of corruption in the Zelensky phone call, that would lend legitimacy to his concerns, even if he stood to benefit politically from an investigation of Biden. At the least, that would make the idea of removing the president from office for those concerns seem ridiculous.

There appears to be widespread interest among Republicans, House and Senate, in finding out more about the Biden business. In an interview with Hugh Hewitt Wednesday, Oklahoma Republican Sen. James Lankford said, "Hunter Biden is a key issue here that everyone doesn't want to deal with, and all the Democrats have said that's irrelevant ... We need to actually get any details there, and those details have not come out, to say the least."

It seems reasonable to expect to expect a fight over the facts of the Biden case. Democrats will argue that the Bidens are totally clean, or mostly clean, or even if they're not clean that their actions are irrelevant. Republicans will try to find inappropriate conduct on the Bidens' behalf and, if possible, use it in the president's defense.

Those are by no means all the factors at work in the impeachment fight. But each is important, and each will help shed light on the biggest question of all: Did the president act improperly in the conversation with Zelensky? And if he did, was the impropriety of a type that merits criticism from Democrats, and perhaps some Republicans, or was it of a type that merits impeachment and removal from office? Democrats want to move quickly with impeachment. But answering those questions could take some time.

