The Note: President Trump’s instincts put to the test with SCOTUS pick, NATO summit Now comes a legacy-defining week -- at home and abroad.

The TAKE with Rick Klein

Washington has gotten used to President Donald Trump as a disruptor, with political instincts that push him toward division and conflict.

Now comes a legacy-defining week that will test those instincts, at home and abroad.

Trump's NATO ambassador, Kay Bailey Hutchison, is promising a NATO summit that will emphasize the alliance's "strength and unity." It will be up to the president to make good on that theme, at a moment when trade wars are beginning to rage, a summit with Vladimir Putin looms, and the U.S. finds itself increasingly isolated.

And with his nomination of a Supreme Court justice Monday night, President Trump has a chance to unite at least his own party – or make the kind of choice top Senate Republicans have warned him against.

"They can get anybody confirmed," Leonard Leo, the former Federalist Society chief who is advising the president on judicial nominations, said on ABC's "This Week," referring to potential teamwork by the White House and Senate Majority Leader Mitch McConnell.

Leo might be right. But not necessarily, now that the nomination will move from hypotheticals to a real person with a very real record.

The RUNDOWN with MaryAlice Parks

First on ABC News – The conservative political advocacy organization, Judicial Crisis Network, plans to launch another major ad campaign with spots online and on cable TV promoting President Trump's nominee for the Supreme Court as soon as the president makes his public announcement.

The group is set to spend $1.4 million on the additional ads, according to spokespeople for the organization. The ads will feature biographical information highlighting the president's choice, and they will run for one week in four states: Alabama, Indiana, North Dakota, and West Virginia.

Three of those states have something in common: competitive Senate races with sitting Democrats defending their seats in states the president carried.

These "red state" Democrats up for reelection could swing the outcome if they back the nominee. They will continue to face tough political pressure to vote in favor of the pick, and might be enticed to, especially if a "no" vote will not actually stop the nomination from going through.

With this new ad, the Judicial Crisis Network will have spent a total of $2.4 million in national cable, broadcast and digital ads, while groups on the other side, specifically pro-choice and women's health care groups, continue to ramp up and plan opposition ads as well.

The TIP with Jonathan Karl and John Santucci

Multiple sources tell ABC News the final four individuals President Trump is considering for the Supreme Court vacancy are Brett Kavanaugh, Thomas Hardiman, Amy Coney Barrett and Raymond Kethledge.

Hardiman made a comeback on the shortlist this weekend, in part because of the president's sister, Judge Maryanne Trump Barry, who serves with Hardiman in the same circuit. Hardiman was beat out by Neil Gorsuch the last time a vacancy opened on the Supreme Court.

But the president, who has been consulting with family, friends and advisors this weekend while in Bedminster, N.J., could change his mind at the last minute.

"I'll be deciding tonight or tomorrow sometime by 12 o'clock and we're all going to be meeting at 9 o'clock," Trump said to reporters while boarding Air Force One Sunday, signaling that he still had not made a final decision.

The sources all stress, though, that the president will stick to the plan and deliver his pick tonight in primetime.

Trump's aides have prepared briefing books and booked television spots for whomever he picks, anticipating that they'll have little time to spare between his decision and the reveal.

WHAT YOU NEED TO KNOW TODAY

President Trump is expected to announce his Supreme Court nominee at 9:00 p.m. in the East Room of the White House.

Secretary of State Mike Pompeo holds a press availability during his foreign trip later this morning.

A status hearing for former Senate Intelligence staffer James Wolfe, who is facing three counts of lying to investigators about contacts he had with journalists, will take place at U.S. District Court for the District of Columbia.

U.S. Army Sgt. Elmore Goodwin, whose remains were missing in Korea since 1950, will be buried at Arlington National Cemetery.

QUOTE OF THE DAY

"First of all, nobody really knows." — Leonard Leo, the president's top Supreme Court adviser, on the likelihood that President Trump's SCOTUS candidates will oppose Roe v. Wade.

NEED TO READ

Trump narrows Supreme Court nominee to 4 names ahead of today's announcement. Multiple sources tell ABC News that as of Sunday, the final four individuals Trump is considering for the vacancy are Brett Kavanaugh, Amy Coney Barrett, Raymond Kethledge and Thomas Hardiman. (Benjamin Siu) https://abcn.ws/2NCkz3J

Senate Dem on Trump's court pick: 'I've never seen a president...make himself a puppet of outside groups'. President Trump's top outside adviser on his Supreme Court nomination said he's "very confident" Republicans can "get anybody confirmed," but a leading Democratic senator suggested that the president is making himself "a puppet" by selecting a Supreme Court nominee from a list compiled by conservative groups. (Will Parsons and Quinn Scanlan) https://abcn.ws/2m4mf9E

Trump administration deals another potential blow to Obamacare by freezing risk adjustment payments. The Trump administration announced on Saturday another potential blow to the Affordable Care Act -- the freezing of risk-adjustment payments that help stabilize insurance pools in the marketplace. The news comes in the wake of a ruling by a U.S. District Court judge in New Mexico that says the Center for Medicare and Medicaid Services payment program is legally flawed. (Meridith McGraw) https://abcn.ws/2KDKgD7

Trump legal team 'close to determining' that president won't sit down with Mueller: Giuliani. Rudy Giuliani, responding to George Stephanopoulos on "This Week" Sunday on whether Trump's legal team has determined if the president will sit down for an interview with Robert Mueller: "We have not. We're close to determining that." (Quinn Scanlan) https://abcn.ws/2zluXJV

Supreme Court decision to uphold travel ban causes anxiety, uncertainty for international students, advocates say. The recent Supreme Court decision upholding the Trump administration's controversial travel ban has students and institutions on edge, advocacy groups say, because of the lasting and crippling effect it could have those seeking education in the United States. (Karolina Rivas) https://abcn.ws/2m0yfc1

Trump's Mar-a-Lago asks to hire 61 additional foreign workers using visa program. There's "help wanted" at The Trump Organization's Mar-a-Lago Club in Palm Beach, Florida. But the company is looking outside of the United States to fill 61 open positions at what the president often refers to as the "Winter White House." (Shannon Crawford and Soo Rin Kim) https://abcn.ws/2KRn5B9

Judge requests list of migrant children who remain separated from their families by Saturday. In a hearing late Friday afternoon, the judge requested a case-by-case list from the government by Saturday, 5 p.m. PT, of around 100 children under 5 who still need to be reunified with their parents, and on Monday morning will rule if a reunification deadline can be extended for some of those cases. (Luke Barr) https://abcn.ws/2MXyvEn

2017 marks historic drop in refugee resettlement. For the first time in almost 40 years, the United States is resettling fewer refugees than the rest of the world, according to a new study by Pew Research Center. (Lee Harris) https://abcn.ws/2L32xFR

Progressive Democrats increasingly criticize Israel, and could reap political rewards. For decades it was seen as too politically risky, but this midterm cycle a growing number of Democratic candidates have begun openly criticizing some of Israel's policies. (Roey Hadar) https://abcn.ws/2Nx6p3A

FiveThirtyEight dives into how each of the reported four people on President Trump's SCOTUS shortlist could affect the highest court in the land, based on their pasts. https://53eig.ht/2KR1Xyl

Ahead of a double-header of summits — first with NATO allies and then a sit-down with Russian President Vladimir Putin — NATO leaders are worried about "a full crackup of the alliance," the Washington Post reports. "The biggest of the allies doesn't just have a disagreement with us, but he actually seems willing to walk away," European Council President Donald Tusk told European leaders last month. https://wapo.st/2NA1j6U

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.