In today's newsletter: Mike Johnson fights to maintain his role as House Speaker. More details about the New Orleans attacker's motive and background come to light. And South Korea's president defies an arrest warrant over his botched martial law declaration.

Here's what to know today.

It’s the first day of the 119th Congress — and with it, two parts of the Republican trifecta of House, Senate and White House control are falling into place. And on Monday, the fourth anniversary of the Jan. 6 riot at the U.S. Capitol, lawmakers are scheduled to certify President-elect Donald Trump’s election victory.

But first, the House will need to choose a leader. Speaker Mike Johnson, who won his party’s nomination for the job in November and has been endorsed by Trump, still faces an uphill climb to win the gavel for a full two-year term. Because of the GOP’s 219-215-seat majority, just two Republican defections could derail his bid.

If no Republican can secure a simple majority, the chamber would be unable to conduct any business, which could keep members-elect from being sworn in, House committees from being constituted and bills from being introduced or voted on.

Read more about Congress’ first day, and follow our live blog for updates throughout the day.

After the House chooses a speaker, Republicans will have a tall to-do list when it comes to advancing Trump’s agenda.

This month, the U.S. is poised to hit the debt ceiling and will begin to use “extraordinary measures” to prevent a default. That’ll likely buy Congress a few months, but members will have to extend the debt ceiling sometime this year.

Congress also faces a government funding deadline on March 14 — and if history is any guide, House Republicans will have to work with Democrats to find enough votes to pass a bill and garner the 60 votes needed to pass in the Senate.

Meanwhile, the GOP wants to move quickly on Trump-backed legislation on immigration, energy and taxes, but disagreements within the party are already spilling out into the open.

Read more about the major tasks that lie ahead.

More coverage:

ISIS-inspired New Orleans attacker leaves family, friends stunned

When Bourbon Street reopened, the sights, bright lights and sounds were as usual. But a heavy law enforcement presence, makeshift memorial and light crowds were reminders of the deadly attack that took place a day before, when a driver plowed through crowds of revelers and killed 14 people. The victims included a teen who had just finished his first semester at the University of Alabama, a former Princeton University football player and single mother who had just been promoted at her job.

Yesterday, authorities shared more information about the attacker, Shamsud-Din Jabbar, including that he was “100% inspired by ISIS.” Jabbar, who was killed in a shootout with police, posted a series of Facebook videos shortly before the attack saying he had originally planned to hurt his family and friends but pivoted when he grew concerned that news and headlines would not focus on the “war between the believers and the disbelievers,” said Christopher Raia, a deputy assistant director of the FBI’s counterterrorism division.

Jabbar, a 42-year-old from Texas, served in the Army on active duty from 2006 to 2015 and then in the Army Reserve from 2015 to 2020, according to three U.S. defense officials. He had been working for Deloitte in a staff-level role since 2021, the company confirmed.

"Sham," as he had been known, impressed an Army commander with his "discipline and dedication." A former classmate remembered him as "very grounded, reserved, quiet." Jabbar's half-brother remembered how he stepped up to care for their father after a stroke.

But after Jabbar’s time in the military and as he worked to climb the corporate ladder, his life began to deteriorate as he faced severe money problems and a third divorce. At some point, he fell under the sway of ISIS. Family and friends were left shocked and confused.

More coverage of the attack in New Orleans:

Man who died in Cybertruck explosion ID'd

The man who died in a Tesla Cybertruck explosion outside of Trump Hotel in Las Vegas on New Year’s Day was a decorated master sergeant in the U.S. Army’s elite special forces unit. At a news conference yesterday, officials with the Clark County/Las Vegas Metropolitan Police said that the person’s body was “burned beyond recognition” but identification belonging to Matthew Alan Livelsberger was found at the scene. Livelsberger died from an apparent self-inflicted gunshot wound to the head, Sheriff Kevin McMahill said.

An Army spokesperson said Livelsberger was assigned to the U.S. Army Special Operations Command on approved leave from his base in Germany. His career included deployments to the Republic of Congo in 2014, Ukraine in 2016, Tajikistan in 2016 and Afghanistan in 2017, 2018 and 2019.

The incident is being investigated as a possible terrorist attack, three senior law enforcement members said. Authorities are still searching for a motive. The Cybertruck in the Las Vegas explosion and the pickup truck used in the deadly attack in New Orleans were rented through the same app, called Turo, but federal officials said yesterday that they had not found any association between the two events.Here’s what else we know.

South Korea president defies arrest warrant

Authorities in South Korea will have to try again to arrest President Yoon Suk Yeol after they failed to enforce an unprecedented warrant over his botched attempt to declare martial law. After a more than five-hour effort that ended around 1:30 p.m. Friday local time, investigators and police officers left Yoon’s official residence in central Seoul. They cited safety concerns as they were blocked by Yoon’s presidential security detail, which told NBC News that it was required by law to protect the president. A growing crowd of Yoon’s conservative supporters were also outside the residence and tried to form a “human shield” to protect him from arrest. Many held up U.S. flags and “Stop the Steal” signs, a slogan adopted from President-elect Donald Trump’s false claims of election fraud in 2020.

Yoon was impeached last month after declaring emergency martial law in the country, only to reverse his order hours later. While he is not the first South Korean president to be impeached, he would be the democracy’s first sitting president to be arrested.

To the moon, an asteroid and beyond

One storyline I’m keeping an eye on in the new year: the return of two NASA astronauts whose weeklong trip to the International Space Station has turned into what is now slated to be a nine-month stay. But there’s plenty more to pay attention to. Science reporter Denise Chow lists a few of the missions we can expect to see, like moon launches, an investigation into the origins of the universe and a first-of-its-kind mission to collect samples of an asteroid. Here’s what else.

— Elizabeth Robinson, newsletter editor

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Thanks for reading the Morning Rundown. Today's newsletter was curated for you by Elizabeth Robinson.

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