Good morning from the WSJ Washington Bureau. Today marks the 18th anniversary of the Sept. 11 attacks. In today's edition, a look at U.S. national security, data on household incomes and presidential candidates' travel.

Trump's Day: President Trump will participate in a 9/11 observance ceremony at the Pentagon today and will observe a moment of silence at the White House. This morning, he renewed his call for lower interest rates and his criticism of the Federal Reserve.

NC Race: Trump ally Dan Bishop won a North Carolina congressional seat in a rare do-over election closely watched by Democrats and Republicans as a bellwether for 2020.

North Korea: Missile tests and strained alliances complicate the path to nuclear deal. Tuesday's departure of  White House national security adviser John Bolton adds another layer of complexity to the situation. 

President Trump dismissed John Bolton, his national security adviser, mere hours after a debate about Afghan peace talks. That contentious disagreement became the latest of many disputes over foreign policy that exposed differences so severe that the two couldn’t even agree on how the ouster happened, Michael C. Bender and Vivian Salama report.

Mr. Trump has removed one of the last dissenting voices on his impulses and instincts. Mr. Bolton’s exit could remove a barrier to a meeting at the United Nations with Iran’s president later this month, or to talks with members of the insurgent Afghan Taliban movement, Vivian Salama and Isabel Coles report.

Mr. Bolton’s departure roils the Trump national-security team once again—but also represents something far broader: It underscores a significant turn in Republican national-security philosophy, at least as Mr. Trump envisions it today, writes Gerald F. Seib. 

The administration unveiled new counterterrorism powers on Tuesday, and imposed sanctions on dozens of individuals and entities allegedly involved with terror groups, Ian Talley reports. 

Here are six key disagreements they had:

Lawmakers remain divided over a legislative path to reduce mass shootings. Republicans are looking to President Trump for guidance—and political cover—before taking up any gun legislation, while Democrats are pledging to press ahead with their own measures, Natalie Andrews, Lindsay Wise and Catherine Lucey report.

Justice Sonia Sotomayor said she is working to build ties with Mr. Trump’s Supreme Court appointees. Justice Sotomayor told a judicial conference that despite sharp ideological differences with Justices Neil Gorsuch and Brett Kavanaugh, building such relationships could moderate the court's shift to the right, Jess Bravin reports.

The ambiguity of the nature of the House Judiciary Committee’s investigation into President Trump appears to be an attempt to bridge the divide between Democrats who support and oppose impeachment.

The Judiciary Committee is expected to vote on Thursday to set procedures for “its investigation to determine whether to recommend articles of impeachment.” Whether that investigation constitutes an impeachment inquiry seems, so far, to depend on whom you ask.

Rep. Jerrold Nadler (D., N.Y.), the chairman of the Judiciary Committee, has previously said the panel is already engaged in “formal impeachment proceedings.” But House Speaker Nancy Pelosi (D., Calif.), speaking to reporters on Monday, said that the investigation is the same as it has always been.

“This investigation has been happening for a long time,” she said. “We’re legislating, we’re investigating as we have been, and we’re litigating.”

For members facing pressure from constituents and groups demanding impeachment, the evolving terminology provides political cover. Need to Impeach, a pro-impeachment group that is working with other activist groups to pressure Democrats to support opening an inquiry, applauded the Judiciary Committee for voting on the procedural changes.

The Congressional Progressive Caucus, a key bloc of House Democrats, on Tuesday released a statement endorsing “the House Judiciary Committee's current formal impeachment investigation and the adoption of the Resolution of Investigative Procedures.” More than half of House Democrats support impeachment.

But lawmakers in Republican-leaning districts who are still wary of endorsing impeachment—and whom Mrs. Pelosi is seeking to shield from political backlash—can still maintain political distance from a full-throated impeachment procedure. Those Democrats can argue that considering whether to impeach the president is not the same thing as impeaching the president—though Republicans have disagreed.

Write to Andrew Duehren at andrew.duehren@wsj.com

Concern over high drug prices is driving proposals this fall from both Republicans and Democrats ahead of the 2020 election. The developments signal a shift in Washington that has alarmed the pharmaceutical industry, which long enjoyed the protection of important Republicans who are now signaling they may take the industry on over the price issue, Stephanie Armour and Andrew Duehren report.

The number of Americans without health insurance climbed to 27.5 million in 2018, according to new federal data that show the first increase since the passage of the Affordable Care Act. The increase comes amid Trump administration efforts to curtail the Obama-era health law.

Health insurers are making their biggest payout ever. They're expected to pay $743 million to consumers this month—more than four times the amount paid out last year—under an ACA rule, report Anna Wilde Mathews and Stephanie Armour.

Joe Biden's rivals in the Democratic primary are ramping up attacks on him as he continues to lead in national polls, saying he is too mistake-prone and too safe a choice to battle Mr. Trump. At the debate on Thursday, the former vice president will seek to emphasize his work to accomplish "progressive change," and highlight a divide in the field between “those who want to build on the Obama legacy and those who want to attack it," a senior Biden campaign adviser tells WSJ's Ken Thomas.

The administration plans to require Fannie Mae and Freddie Mac to begin paying a fee for support from the Treasury Department in exchange for a change to the mortgage-finance companies’ status that will allow them to retain their earnings, reports Andrew Ackerman.

American incomes remained essentially flat in 2018 after three straight years of growth, according to Census Bureau figures, report Janet Adamy and Paul Overberg. The poverty rate in 2018 was 11.8%, marking the first time it fell significantly below its 2007 level.

• In the wake of the departure of national security adviser John Bolton, Iran's president urged the U.S. to put aside "warmongers." (Associated Press)
• Half of likely Democratic voters think a woman would have a harder time running against President Trump next year than would a man, a new poll shows. (USA Today)
• The growing influence of French President Emmanuel Macron was on display as the European Commission unveiled a new leadershp team. (Bloomberg)

This newsletter is a production of the WSJ Washington bureau. Our newsletter editors are Tim Hanrahan, Kate Milani, Troy McCullough and Daniel Nasaw. Send feedback to capitaljournal@wsj.com. You can follow politics coverage on our Politics page and at @wsjpolitics on Twitter.