President Trump made small talk with the Irish prime minister as they sat in the Oval Office in mid-March, accompanied by a handful of senior American and Irish officials.

Trump, who wore a green tie and filled his jacket pocket with a clump of shamrock to honor the Irish leader's annual St. Patrick's Day visit, turned with a half-smile to his hawkish national security adviser John Bolton, according to two sources who were in the room.

• "John," Trump asked, "Is Ireland one of those countries you want to invade?"

Behind the scenes: The joke captured how Trump often privately interacts with Bolton, even occasionally in front of foreign heads of state. "John has never seen a war he doesn't like," Trump said in a recent Oval Office meeting, according to a source with direct knowledge.

• Trump often privately ribs Bolton about his public persona, according to sources who've been in Situation Room meetings with them. (Trump teases most of his top advisers and officials in different ways. For example, during discussions of trade with China, Trump has needled Treasury Secretary Steven Mnuchin in front of other senior officials: "Steve, you're so weak. You're so weak. You didn't used to be this way in business. You're so weak now.")
• In a SitRoom meeting last year, Trump's national security team was going around the table discussing a topic that was nuanced and had no relation to major military action. A source in the room said that as the conversation got to Bolton, Trump joked: "Ok, John, let me guess, you want to nuke them all?" People in the room "died laughing," the source said.

Between the lines: That's not to say that Trump's view of Bolton is rose-colored. People close to Bolton have recently worried about his job security. Yet while Bolton can rub Trump the wrong way — a well-documented dynamic — and while internal and external Bolton critics often complain to Trump that Bolton will drag him into an unwanted war, Trump still defends his national security adviser in private conversations with critics.

• "He gets quite touchy when you bring it up," said a person who has criticized Bolton to the president. "He doesn't want anyone to believe he's anybody's pawn."

Trump's Bolton Doctrine: Trump has a strongly held theory of Bolton's value, according to senior administration officials and advisers to the president, including people who have privately recommended to Trump that he fire Bolton. Seven sources who have discussed Bolton with Trump told me the president says having Bolton on his team improves his bargaining position and gives him a psychological advantage over foes like Iran and North Korea.

• "Trump thinks that Bolton is a key part of his negotiating strategy," said the same person who described Trump as "touchy" about Bolton. "He thinks that Bolton's bellicosity and eagerness to kill people is a bargaining chip when he's sitting down with foreign leaders. Bolton can be the bad cop and Trump can be the good cop. Trump believes this to his core."
• A former senior administration official who remains close to Trump said Bolton's presence on the team "makes other people know that there is going to be that type of voice in the room."

Trump occasionally flips the good cop, bad cop script with his national security adviser. In the expanded bilateral meeting with the Dutch prime minister on Thursday in the Cabinet Room, Trump was criticizing European nations, including the Dutch, for not spending enough to meet their NATO obligations, according to a source familiar with the meeting. At one point, after Trump gave this criticism, he turned to Bolton, who was sitting to his right and said, "but, John, you love NATO right?"

• Bolton gave a very brief defense of NATO. Then Trump started drilling down again on his dissatisfactions, the source said.

Go deeper: Read my full story on Trump's relationship with Bolton, including previously unreported scenes from the Situation Room.

Former special counsel Robert Mueller will make his much-hyped appearance on Capitol Hill Wednesday, but neither party expects to learn anything new from Mueller's 5-plus hours of public testimony, according to Axios' Alayna Treene's conversations with more than a dozen members of Congress and staffers involved in the hearing preparations.

The bottom line: Each party sees the hearings as a political opportunity — whether it be Democrats trying to stoke support for impeachment or Republicans seeking to sow distrust in the Justice Department's Russia investigation.

What to expect: The House Intelligence Committee hearing will focus on Volume 1: Russian interference in the 2016 presidential election, while the House Judiciary Committee will focus on Volume 2: possible instances of obstruction of justice by President Trump.

Democratic members on the committees, who have been thirsting for months to have Mueller testify publicly, told Alayna they see the hearing as an opportunity for Mueller to educate the American public on the most damaging aspects of his report.

• "The success will be in the TV ratings," Rep. Ro Khanna (D- Calif.), who will not be questioning Mueller, said. "The more Americans that watch, the more successful it is."
• "Most Americans haven't had a chance to read a 400-page report," House Intel Chairman Adam Schiff (D-Calif.) told Axios. "This will be the first time they hear from the man who did the investigation himself, not filtered through the misrepresentations of [Attorney General] Bill Barr or anybody else."
• "My fantasy is when I get my 5 minutes, I'm just going to have him read certain excerpts from his report. And I think that will be very powerful," said Rep. Jackie Speier (D-Calif.), a member of the Intel committee.

Why it matters: Roughly 90 Democrats publicly support impeaching Trump, and some lawmakers think that once Mueller opens his mouth, the percentage of Americans who support impeachment will spike.

The other side: GOP committee aides and key members — including Reps. Andy Biggs (Ariz.) and Jim Jordan (Ohio), both members of the Judiciary committee — told Axios that Republicans' biggest goal is pinpointing when Mueller knew there was no collusion between the Trump campaign and Russia, and why he didn't let the public know sooner that the president wasn't a Manchurian candidate.

• Mueller's report didn't establish a criminal conspiracy between the Trump campaign and Russia.

Go deeper: Read Alayna's full story in the Axios stream.

Several of the leading Democratic presidential contenders told Alayna that, if elected, they would go further than the Trump administration in confronting China over its imprisonment of more than 1 million Uighur Muslims in its Xinjiang region.

Why it matters: It has been 2 years since the internment camps — which activists say are designed to erase the Uighur identity — first came to light internationally. The Trump administration has considered imposing sanctions on Chinese officials over the camps, but has yet to act amid threats of retaliation.

Over the last week, Alayna asked the top 2020 Dem candidates how they would address the situation in Xinjiang if elected president.

• Specifically, would they support putting companies that build the Uighur detention camps and their surveillance system on the Commerce Departments' Entity List? And would they use the Global Magnitsky Act to sanction the people running the camps?

State of play:

• Would support, at a minimum, both measures: Former VP Joe Biden; Sens. Bernie Sanders and Cory Booker; South Bend, Indiana, Mayor Pete Buttigieg; and former HUD Secretary Julián Castro.
• Proposed an alternative strategy: Sens. Elizabeth Warren and Kirsten Gillibrand.
• Worth noting: Warren is the only senator running for president who signed a bipartisan letter to Trump administration officials in April urging greater export controls and Magnitsky sanctions against Chinese officials overseeing the Xinjiang policy.
• Did not respond to multiple requests for a comment: Sens. Kamala Harris and Amy Klobuchar.
• Worth noting: Harris and Michael Bennet are the only senators running for president who did not co-sponsor the Uighur Human Rights Policy Act in January.
• Declined to comment: Former Congressman Beto O'Rourke.
• Read the candidates' full responses here.

Go deeper: Read Alayna's full story in the Axios stream.

Impeachment on Aisle D ... House Judiciary Chairman Jerry Nadler made his intentions abundantly clear in his conversation this morning with Fox News Sunday host Chris Wallace.

Previewing Wednesday's Mueller hearing, Nadler told Chris:

• "The [Mueller] report presents very substantial evidence that the president is guilty of high crimes and misdemeanors and we have to present — or let Mueller present — those facts to the American people and then see where we go from there."

This is the last week of session before the House breaks for August recess. The Senate will be in session the week of July 29. Members of leadership hope they can reach an agreement with the White House to raise budget caps and the debt limit, but they are running out of time.

The House will consider the Rehabilitation for Multiemployer Pensions Act, commonly referred to as the "Butch Lewis Act." The bill, if passed, would provide interest-only loans for 29 years and "a balloon repayment" in the 30th year to troubled multiemployer defined benefit plans.

• The House will also consider the Homeland Security Improvement Act. The measure, if passed, would provide independent oversight of border security activities and improve training for officers of Customs and Border Protection and Immigration and Customs Enforcement.
• A Democratic leadership aide said the House is expected to consider additional legislation to deal with the current humanitarian crisis on the southern border.

The Senate will vote on Tuesday to permanently extend the 9/11 victims fund. The bill is expected to pass. The Senate will also vote to confirm the following nominees in this order, per a Republican leadership aide:

• Mark Esper for Secretary of Defense.
• Stephen Dickson for Administrator of the Federal Aviation Administration for a 5-year term.
• Wendy Williams Berger as a Judge for the Middle District of Florida.
• Brian Buescher as a Judge for the District of Nebraska.

President Trump's schedule, per a White House official:

• Monday: Trump will meet with the Pakistani Prime Minister Imran Khan.
• Tuesday: Trump will speak at Turning Point USA's "Teen Student Action Summit." The president will also have lunch with Secretary of State Mike Pompeo and meet with Republican senators.
• Wednesday: Trump will have lunch with Vice President Mike Pence. He will also address a fundraiser in West Virginia. 
• Thursday: Trump will participate in "Pledge to America's Workers — One Year Celebration."