Philip Ewing

Each week — and some days, it seems, each hour — brings more clarity to the picture of the Ukraine affair and the political crisis it sparked in Washington over impeachment.

But some of the biggest questions still don't have answers.

Here's a look at where the saga stands, what investigators want to learn and what major decisions still must be reached before the fever breaks.

The Ukraine affair

No one disputes the basic outlines of the Ukraine affair, including Trump:

Updated at 6:45 p.m. ET

House Speaker Nancy Pelosi did not rule out a vote by the full chamber on its impeachment inquiry into President Trump — but she restated her belief on Friday that none is required for it to move ahead.

Pelosi, D-Calif., said on a trip to Atlanta that she was unmoved by calls from the White House for a full vote. Trump said earlier in the day that he would send a letter to the speaker, which was expected to demand action by the full House.

House Democrats are set to launch a new phase of their impeachment inquiry on Thursday when former Ambassador Kurt Volker, until recently a top State Department representative to Ukraine, is scheduled to meet with investigators.

Then, on Friday, the intelligence community's inspector general, Michael Atkinson, is due on the Hill.

More witnesses are expected next week, all for depositions behind closed doors with members of Congress and their staff.

A tumultuous week in Washington has set the stage for an intense new congressional investigation into President Trump — and what could prove to be a historic clash between the White House and Congress.

The outlines are now clear about conduct that no one, including Trump, disputes: The president asked his Ukrainian counterpart to investigate the family of Vice President Joe Biden, a potential political rival in the 2020 presidential election.

Updated at 12:08 p.m. ET

The nation's top spy told lawmakers on Thursday that he supports the whistleblower whose complaint sparked the Ukraine affair but said he struggled to deal with how to handle the case inside the Trump administration.

Acting Director of National Intelligence Joseph Maguire told the House intelligence committee in an open hearing that he believed the whistleblower and the spy world's inspector general had acted in good faith and that he has tried to handle a unique situation as best he could.

Updated at 5:25 p.m. ET

President Trump told Ukraine's president that "a lot of people want to find out" about the activities of former Vice President Joe Biden's family in Ukraine and asked its leader to be in touch with lawyer Rudy Giuliani and Attorney General Bill Barr.

That's according to a briefing for correspondents about the contents of the July 25 phone call, on Wednesday at the Justice Department.

Updated at 5:25 p.m. ET

President Trump and his opponents jockeyed for advantage on Monday as Washington girded for a drawn-out conflict over the White House and Ukraine.

Trump and his aides sought to throw the spotlight on former Vice President Joe Biden and his son, Hunter, who they said might be connected with what they called "corruption" in Ukraine — although Biden's camp insists those allegations have been debunked.

Updated at 4:53 p.m. ET

President Trump's former campaign manager jousted with House Democrats on the Judiciary Committee Tuesday in a combative hearing that each side hoped might strengthen its narrative about the legacy of the Russia imbroglio.

President Trump spiked the peace negotiations for a war he's desperate to end and sacked the national security adviser who shaped much of his foreign policy in Asia and the Middle East.

Where does the Trump administration's foreign policy go from here?

Until Saturday, one path, at least, appeared clear: Washington was inching closer to some kind of agreement with the Taliban to end the 18-year conflict in Afghanistan.

Updated at 4:57 p.m. ET

President Trump has fired national security adviser John Bolton, the lifelong proponent of American hard power, after months of division between the men over the direction of foreign and national security policy.

Trump announced the news Tuesday on Twitter.

Americans are preparing more than ever to safeguard voting as the nation looks ahead to the Democratic primaries and the general election next year.

What no one can say for certain today is whether all the work may turn out to be superfluous — or whether it'll be enough.

Security experts have warned about the prospect of a new era of high quality faked video or audio, which some commentators worry could have deeply corrosive effects on U.S. democracy.

Here's what you need to know.

What are "deepfakes?"

Foreign interference didn't begin in 2016. It didn't end with that election. And U.S. officials expect it to remain an issue through the 2020 elections as well.

Here's what you need to know.

Voting systems in the United States have come a long way since the hanging chads of the 2000 recount in Florida — but now cybersecurity is as big a concern as ballot fidelity.

Here's what you need to know.

The good news

President Trump defended the idea of buying Greenland — derided by critics within the United States and rejected by Denmark, which controls it — in part by saying the idea first came from President Harry Truman.

Updated at 4:32 p.m. ET

President Trump abruptly dropped his intention to nominate Rep. John Ratcliffe, R-Texas, to serve as director of national intelligence on Friday.

Updated at 2:23 p.m. ET

The Federal Election Commission is considering proposed new rules to outlaw exchanges like the one that took place when a Russian delegation visited Trump Tower in 2016 to offer Donald Trump's campaign "dirt" on Democrats.

Although U.S. law already forbids contributions from foreigners to American political campaigns, President Trump has said that the meeting taken by his son Donald Trump Jr. and others was business as usual and that everybody in politics accepts "opposition research."

Updated 1:35 p.m. ET

Rep. John Ratcliffe is President Trump's choice to become the next top leader of the U.S. intelligence community.

The Texas Republican thanked Trump on Twitter following the president's earlier announcement, also on Twitter, that Ratcliffe is his nominee to replace outgoing Director of National Intelligence Dan Coats.

Former special counsel Robert Mueller did what Democrats wanted him to do on Wednesday — the question now is how much difference that may make.

Mueller's hearings did not feature a telegenic star who could deliver a message as exuberantly as President Trump's opponents hoped.

Updated at 4:56 p.m. ET

Peril from foreign interference in American elections will persist through the 2020 presidential race, former special counsel Robert Mueller warned on Wednesday.

Asked whether Russia would attempt to attack future U.S. elections, as it did in 2016, Mueller replied: "They're doing it as we sit here."

Mueller didn't detail a prescription for how he believes Congress or the United States should respond, but he recommended generally that intelligence and law enforcement agencies should work together.

Updated at 4:56 p.m. ET

Peril from foreign interference in American elections will persist through the 2020 presidential race, former special counsel Robert Mueller warned on Wednesday.

Asked whether Russia would attempt to attack future U.S. elections, as it did in 2016, Mueller replied: "They're doing it as we sit here."

Mueller didn't detail a prescription for how he believes Congress or the United States should respond, but he recommended generally that intelligence and law enforcement agencies should work together.

Robert Mueller's appearance in Congress this week will be a hinge moment — the question is which way it might swing the political trajectory in Washington.

The Democrats who have negotiated for months to get Mueller to appear, and wound up compelling him with a subpoena, want Americans to watch the former special counsel tell his story on Wednesday in TV-friendly soundbites that erode support for President Trump.

Director of National Intelligence Dan Coats has installed a new czar to oversee election security efforts across the spy world, he announced on Friday.

A veteran agency leader, Shelby Pierson, has been appointed to serve as the first election threats executive within the intelligence community, or IC, Coats said.

"Election security is an enduring challenge and a top priority for the IC," said Coats.

Updated at 2:13 p.m. ET

President Trump has conflated an infamous practice in and among political campaigns — "opposition research" — with foreign election interference like that launched by Russia against the United States in 2016.

Are they the same thing? Is foreign interference just a kind of "oppo research," as Trump said in an interview with ABC?

Updated at 5:53 p.m. ET

The separation-of-powers standoff between Congress and the executive branch deepened on Wednesday over a dispute about access to materials involving the controversial citizenship question planned for the 2020 census.

The Justice Department notified the House oversight committee that it's withholding documents sought by the panel's chairman because it says they're shielded by executive privilege — the doctrine that permits an administration to conceal some of its internal workings.

Updated at 6:35 p.m. ET

The House has authorized its committee leaders to pursue civil contempt cases to get information for their myriad investigations into President Trump.

Although the vote, 229-191, clears the way for more lawsuits against Cabinet departments, administration officials, bankers, accountants and more, it represented a sidestep from a more aggressive partisan confrontation that might have been.

Updated at 4:30 p.m. ET

The House voted on Tuesday to authorize its committees to sue the Trump administration and others in pursuit of witnesses and documents for their manifold investigations into President Trump.

Updated at 3:25 p.m. ET

The Justice Department is to begin providing documents to the House Judiciary Committee after a dispute over a subpoena — but members of Congress are reserving the ability to continue to pursue contempt litigation down the line.