If you’re wondering why, at the 11th hour, the White House today blocked the congressional testimony of US Ambassador to the EU Gordon Sondland — a $1 million contributor to Trump’s inauguration committee before Trump appointed him — this week’s update to the Trump Russia Timeline at Dan Rather’s News & Guts and Just Security offers an explanation.

It has nothing to do with lawyers’ specious objections based on executive privilege.

It has everything to do with this:

• July 19: Rudy Giuliani tells Kurt Volker, US special representative to Ukraine, that he wants Ukrainian President Volodymyr Zelensky to investigate former Vice President Joe Biden and his son, as well as 2016 election interference by Ukraine. Sondland texts Volker: “Looks like Potus call tomorrow. I spike [sic] directly to Zelensky and gave him a full briefing. He’s got it.”
• July 25: An hour before Trump’s infamous call to Zelensky, Sondland speaks directly with Trump.
• Aug. 9: Volker texts Sondland about Zelensky’s proposed statement reopening investigations relating to the Bidens and the 2016 election: “Mentioned Z making a statement. Can we all get on the phone to make sure I advise Z correctly as to what he should be saying? Want to make sure we get this done right.” At the same time, Sondland is also communicating with the White House about a proposed Trump-Zelensky meeting after Zelensky issues the statement.
• Aug. 13: Volker sends Sondland the proposed Zelensky statement. Sondland responds: “Perfect.”
• Aug. 17: Sondland texts to Volker: “Unless you think otherwise I will return [Zelensky’s aide Andrey Yermak’s] call tomorrow and suggest they send us a clean draft.”

Then things get really interesting.

• Aug. 30: Sondland tells Sen. Ron Johnson (W-WI) of a possible quid pro quo: Zelensky agrees to probe matters related to Ukraine’s involvement in the 2016 US election. In return, Ukraine will receive nearly $400 million in US aid that Trump had been withholding for months.
• Sept. 1: US charge d’affaires for Ukraine, William Taylor, texts Gordon Sondland, US ambassador to the EU : “Are we now saying that security assistance and WH meeting are conditioned on investigations? Sondland responds: “Call me.”
• Sept. 9: Taylor reiterates, “As I said on the phone, I think it’s crazy to withhold security assistance for help with a political campaign.”

By that time, the White House had known for almost a month about the whistleblower complaint alleging that Trump was abusing presidential power for personal political purposes. The CIA’s general counsel had referred the claims to the Justice Department.

Before answering Taylor four hours after receiving his message, Sondland speaks with Trump, according to The New York Times.

Then Sondland — four hours after receiving Taylor’s message — texts back that their conversation should move to phone rather than text.

If you were Trump, would you want investigators in the House impeachment inquiry hearing from Sondland?

Here is a list of the latest update to the Trump-Russia Timeline at Dan Rather’s News & Guts and Just Security:

JAN. 28, 2017: Trump ‘Fawns’ Over Putin

SUMMER 2018: Trump Dismisses May on Russia

JANUARY 2019: Giuliani and Lutsenko Meet in New York

MARCH 20, 2019: Trump Tweets Headline of Ukraine General Prosecutor Lutsenko’s Interview Pushing False Conspiracy Theory

MARCH 28, 2019: Giuliani Prepares List of Complaints About Bidens, Yovanovitch; Gives it to Pompeo

APR. 21, 2019: Zelensky Wins Ukraine Presidential Election; Trump Urges Him to Work With Giuliani on ‘Corruption’ (revision of previous entry)

EARLY MAY 2019: Pompeo Receives Packet of Disinformation Aimed at Bidens, Yovanovitch; Giuliani Later Admits That Some Came From Him

MAY 6, 2019: US Ambassador to Ukraine Recalled (revision of previous entry)

MAY 20, 2019: Trump Tells Pence Not to Attend Zelensky’s Inauguration

MAY 23, 2019: Volker Meets With Trump; Concerned That Giuliani is Providing Negative Information About Ukraine

JUNE 4, 2019: Kushner Sits Next to Zelensky in Brussels

JUNE 18, 2019: Trump Asks China To Investigate Biden

JULY 18, 2019: Volker Learns About Hold on US Assistance to Ukraine

JULY 19, 2019: Giuliani, Volker, Sondland, and Taylor Exchange Text Messages Re: Effort to Get Ukraine to Investigate Bide

JULY 21, 2019: Taylor Flags Zelensky’s Concern About Becoming Involved in US Domestic Politics

JULY 22, 2019: Giuliani Pushes for Trump-Zelensky Call

JULY 25, 2019: Quid Pro Quo In Place For Trump-Zelensky Call

JULY 25, 2019: Trump Calls Zelensky (revision of previous entry)

JULY 25, 2019: Yermak and Volker Text About Giuliani Meeting in Madrid

JULY 26, 2019: TRUMP ASKS BORIS JOHNSON TO HELP UNDERMINE MUELLER

AUGUST-SEPTEMBER 2019: Giuliani Seeking Ukraine Help From Manafort

AUG. 9, 2019: US State Department Seeks Giuliani’s Guidance on Proposed Zelensky Statement; Discuss White House Visit

AUG. 10, 2019: Zelensky Aide Presses for White House Meeting Date

AUG. 13, 2019: Volker and Sondland Exchange Texts About Ukrainian Statement on Corruption

AUG. 14, 2019: CIA General Counsel Confers With White House Lawyer and DOJ; Makes Criminal Referral to DOJ

AUG. 17, 2019: Volker and Sondland Continue Discussions About Ukrainian Statement

AUG. 28, 2019: Ukrainian Expresses Concern About US Reported Withholding of Military Aid

AUG. 30, 2019: Trump Cancels To Meet Zelensky

AUG. 30-31, 2019: Sen. Johnson Asks Trump About Ukraine Quid Pro Quo

AUG. 31, 2019: Pence, Perry, and Sondland Meet With Zelensky in Warsaw

SEPT 1, 2019: Taylor Asks Sondland About Ukrainian Quid Pro Quo; Sondland Says, ‘Call Me’

SEPT. 8, 2019: Taylor Describes Ukraine “Nightmare”

SEPT. 9, 2019: Ambassadors React to Withholding Aid to Ukraine; Trump Involved

SEPT. 25, 2019: Trump Tells Zelensky To ‘Get Together’ With Putin

SEPT. 30, 2019: US Issues Sanctions For Russian Interference

OCT. 1, 2019: Pompeo Defies Congressional Subpoenas

OCT. 1, 2019: Trump Tweets That He Wants to Interview Whistleblower

OCT. 1, 2019: Ukraine Agrees to Formula Favorable to Russia

OCT. 3, 2019: Volker Testifies to Congress, Says He Told Giuliani That Claims About Biden Were False

OCT. 3, 2019: Trump Urges Ukraine and China to Investigate Biden

OCT. 4, 2019: Ukraine Announces Reexamination of Biden Investigation

OCT. 4, 2019: House Subpoenas White House, Asks Pence for Documents

OCT. 5, 2019: Trump Says Perry Prompted Call to Zelensky