 -- WHAT YOU NEED TO KNOW TODAY

This was as big as they come. Donald Trump Jr.'s emails showed he was informed he would be meeting with a "Russian government attorney" for information on Hillary Clinton. His response to the possibility of his receiving campaign help from a foreign government? "I love it."

Trump Sr. is up early, defending his son – "He was open, transparent and innocent. This is the greatest Witch Hunt in political history. Sad!" he wrote on Twitter.

Special Counsel Robert Mueller is paying attention. Former and current officials tell ABC News' Pierre Thomas that Donald Trump Jr.'s meeting with the Russian attorney and Trump's inner circle will very much be part of what is turning into a sweeping investigation.

Don't miss the veep. Vice President Mike Pence's press secretary said Pence was not aware of the Russia meeting, adding this: "He is not focused on stories about the campaign, particularly stories about the time before he joined the ticket."

As for the Hill, today's Christopher Wray confirmation hearings for FBI director will air concerns about President Trump, Russia, leadership and more.

Split-screen Senate: Some Senate Republicans are trying to shrug off the Donald Trump Jr. emails, instead chugging away at health care. Senate Majority Leader Mitch McConnell canceled the first half of August recess with the health care bill still far from being finalized or having the votes.

THE TAKE with ABC News' Rick Klein

The space between "I love it" and "I probably would have done things a little differently" is room enough for Donald Trump Jr. to have blown a hole in a year's worth of representations put forward by the now-president and the team around him. It's enough to galvanize the special counsel's office and congressional investigations into Russian meddling and all that it appears to have triggered in the White House. It figures to dominate today's confirmation hearing for an FBI director nominee who was nowhere near the story but will have to grapple with the fallout inside the agency. President Trump is applauding his son's transparency. But it's transparency in a different sense that makes the already infamous email chain the single-most damning piece of evidence to emerge in the collusion probe. This was a see-right-through-it willingness, on the part of the president's son, to use damaging campaign information he was being told was being offered as "part of Russia and its government's support for Mr. Trump." Everything else in this investigation uses that as a baseline. This scandal has long been about what isn't known, about shoes that could still drop. But this, by itself, was a loud enough stomp to be heard for a long while.

ENTER TRUMP'S PICK FOR FBI DIRECTOR

Chris Wray was nominated to lead the FBI without fanfare. No Rose Garden ceremony or even a speech from the president. The news about him was swallowed in a sea of headlines at the time about what his would-be predecessor, James Comey, was saying on Capitol Hill about his relationship with his would-be boss, the president. So, today's hearing will largely be a public introduction to the man tapped to lead the bureau at this crucial time. Senators will surely have plenty of questions: Would he take a loyalty pledge to the president? Does he think the idea of one is odd? What would he do if the president told him he hoped he would he stop an active investigation? Would he tell someone? Would he consider that sort of line from the president an order? Could it have been obstruction of justice? What does he think of the special investigation now underway? Is it a witch hunt? Did he think it was appropriate that Comey went public with this conclusions about Hillary Clinton's emails and then again with the news that the FBI was reviewing more emails so close to the election? Does he think Donald Trump Jr. may have broken any laws last summer when he thought he might be offered dirt on Clinton so agreed to meet with a Russia lawyer? Wray worked for the Bush administration right after 9/11, so there will be plenty of questions, too, about his beliefs in torture and whether he thinks enhanced interrogations can be legally justified, ABC News' MaryAlice Parks writes.

QUOTE OF THE DAY

"There was nothing to tell. I wouldn't have even remembered it until you started scouring through stuff. It was literally just a waste of 20 minutes, which is a shame." -- Donald Trump Jr. to Sean Hannity speaking about his meeting with Russian lawyer Natalia Veselnitskaya

WHAT TO WATCH TODAY

FBI director nominee Christopher Wray, Trump's pick to replace James Comey, is set for his confirmation hearing on Capitol Hill.

NEED TO READ with ABC News' Daksha Sthipam

Legal experts weigh in on emails released by Donald Trump Jr. ABC News spoke to legal experts about whether Trump broke any laws. The most relevant law, a campaign finance rule, makes it unlawful to "knowingly solicit, accept, or receive" a "contribution" from a foreign national or foreign government, according to experts. Violators can be fined by the Federal Election Commission (FEC), or if they act "willfully," they can be charged with a crime, even a felony. http://abcn.ws/2sPaHsy

White House official: Trump to postpone London visit until 2018. President Donald Trump will no longer be visiting London in his first year as president, a senior White House official confirmed to ABC News Tuesday. The official cited a "scheduling conflict" as the reason behind the change, and said the White House has gotten in touch with the British government to iron out plans for a visit in 2018. http://abcn.ws/2tHirzt

Some voters un-registering after Trump administration's data requests. After the Trump administration's request for voter registration data as part of the newly established Presidential Advisory Commission on Election Integrity, some U.S. states have seen an uptick in citizens' moving to keep their information out of the federal government's hands. http://abcn.ws/2tdGFxT

WHO'S TWEETING?

@Jo_Becker: Want the backstory on what led my colleagues and me to the Trump Jr email scoop? Get it here: http://nyti.ms/2tLPv86

@maggieNYT: Don Jr. advocated Saturday for giving more fulsome response on the Russia meeting, but was overruled, per sources http://nyti.ms/2ubDv1Q

@AliABCNews: Senate Intel chairman @SenatorBurr calls the @DonaldJTrumpJr emails "interesting." Says not clear whether we've seen whole email chain

@desiderioDC: NEW: Grassley writes to Tillerson & Kelly asking for info on how Veselnitskaya was allowed to enter the U.S. http://bit.ly/2uQqx7q

@joshrogin: Exclusive: Next week, Senate Judiciary Committee will hear testimony on Natalia Veselnitskaya and Fusion GPS http://wapo.st/2u7Ywej

The Note is a daily ABC News feature that highlights the key political moments of the day ahead. Please check back tomorrow for the latest.