There's a debate about the value of North Korean leader Kim Jong Un's promise to shut down North Korea's largest nuclear test site as he engages in peace talks with South Korea and President Trump's administration, but a study published in the journal Science on Thursday suggests the Punggye-ri site was largely destroyed after Pyongyang's last nuclear test in September. In the new study, researchers from the U.S., China, Germany, and Singapore created a 3-D model of the site based on space-based radar, and they found that the test tunnels continued caving in for hours and days after the explosion, causing more extensive damage than previously believed.

The damage first discerned at the site, under Mt. Mantap, was "dwarfed" by the subsequent collapses, says Sylvain Barbot, an author of the study from Singapore's Nanyang Technological University and the University of Southern California. "These findings make us infer that a large part of the Punggye-ri test site is inoperable and that further test may require a substantial investment in the construction of another facility elsewhere." Kim told South Korean President Moon Jae-in at this historic summit that two of the site's larger tunnels are still in good condition, Seoul says. Kim is meeting with Trump in Singapore on June 12. Peter Weber

As 2018 winds to a close, "it feels like the whole country is still nursing a hangover from the 2016 presidential election — Trump is still obsessed with Hillary, Mueller is still investigating Trump, and Democrats are about to launch a slew of new investigations into his campaign," Trevor Noah said on Tuesday's Daily Show. "But now, over two years later, we're still about how deep the Russian rabbit hole goes," including the Kremlin's trolls targeting of one particular group. "It turns out, the Russians spent a lot of effort specifically trying to convince black Americans not to vote," Noah said — or to vote for Green Party candidate Jill Stein, same difference.

"Real black American" Dulcé Sloan came out to give her mixed reaction to the news. "Trevor, I feel disgusted, I feel manipulated, and I feel special," she said. "Russia could have gone after anyone — Latinos, Asians, millennials — but they said, We're going after the ones who count: black people. Can you believe that? I mean, some white people actually do think black lives matter." She had some suggestions for Washington. Watch below. Peter Weber

You say border wall, President Trump says "artistically designed steel slats."

On Twitter Tuesday night, Trump declared that he's figured out the real problem Democrats have with funding a wall along the southern border. "The Democrats, are saying loud and clear that they do not want to build a Concrete Wall — but we are not building a Concrete Wall, we are building artistically designed steel slats, so that you can easily see through it .... it will be beautiful and, at the same time, give our Country the security that our citizens deserve. It will go up fast and save us BILLIONS of dollars a month once completed!"

"Build the artistically designed steel slats!" sure doesn't have the same ring to it as "Build the wall!" Catherine Garcia

In a bipartisan vote, the Senate on Tuesday passed the First Step Act, the biggest overhaul of the federal criminal justice system in decades.

The bill passed with a vote of 87-12, and was backed by conservative and liberal groups. Lawmakers spent more than a year negotiating the bill, which creates more rehabilitation programs, eases mandatory minimum sentencing, reduces the three-strike penalty from life in prison to 25 years, and lets some federal inmates earn time credits by taking part in special programs.

Now, the bill moves to the House, where it also has bipartisan support. After the Senate passed the measure, President Trump tweeted that he looks "forward to signing this into law!" Catherine Garcia

Over the course of a decade, the late George H.W. Bush sponsored a boy living in the Philippines who had no idea that the money, letters, and gifts coming to him from the United States were being sent by a former president.

Bush learned about Compassion International, a nonprofit that connects sponsors with children from poor communities, in 2001, the organization's former president, Wess Stafford, told CNN on Tuesday. Bush's security team did some digging, and after vetting Compassion International, they agreed that he could sponsor 7-year-old Timothy. There were some rules, though; he had to use a pseudonym, to protect Timothy from someone who might target him due to his link to Bush.

For 10 years, Bush sent letters — signed "George Walker" — and funds that paid for Timothy's education, activities, and food. Stafford screened Bush's letters, describing them to CNN as being "the most sweet, spirited letters I have read from any sponsor, but he kept giving hints as to who he could be. He was really pushing the envelope." Bush sent photos of his dog, Sadie, and told Timothy that he was invited to the White House for Christmas. Timothy drew pictures for Bush, who in turn sent him sketch pads, colored pencils, and paint, even though gifts were not allowed.

Timothy didn't find out who his sponsor was until he turned 17 and graduated. He was stunned, Stafford said, never having a clue that his pen pal and benefactor was once the president of the United States of America. Catherine Garcia

A panel of eight federal judges on Tuesday dismissed 83 complaints filed against Supreme Court Justice Brett Kavanaugh by "lawyers, doctors, professors, and concerned citizens, among others."

Most of the complaints lodged against him stem from his heated Senate confirmation hearings, with petitioners accusing Kavanaugh of misconduct and making disrespectful statements to senators, Reuters reports. The panel threw out the complaints because the federal law governing judicial conduct does not apply to Supreme Court justices, only lower court judges.

Kavanaugh was a federal appellate court judge when President Trump announced in July he was nominating him for the Supreme Court. Before he was confirmed in October, Kavanaugh was accused by several women of sexual misconduct, allegations that he denied. Catherine Garcia

The U.S. State Department granted a visa on Tuesday to a Yemeni mother fighting to see her dying 2-year-old son at a hospital in San Francisco.

Shaima Swileh's son, Abdullah, has a genetic brain disorder. Her husband, Ali Hassan, is a U.S. citizen, and he brought Abdullah to California in the fall for treatment. As a Yemeni citizen, Swileh was not able to get a visa under the Trump administration's travel ban, and was not allowed to travel to the U.S. with her family. They filed for a waiver, but Abdullah's health began to worsen, and he was put on life support last week.

Hassan wanted his wife to be able to kiss their son one final time, but he also didn't want the toddler to suffer and had given up hope that the waiver would come through. A social worker at the hospital contacted the Council on American-Islamic Relations in Sacramento, and their lawyers sued this week. "This will allow us to mourn with dignity," Hassan said in a statement. Swileh will fly to San Francisco on Wednesday.

Waivers are granted on a case-by-case basis, with applicants having to prove they are not security threats and that their entry is in the national interest. "We hope this case makes the administration realize the waiver process is not working," Basim Elkarra of CAIR told The Associated Press. "Thousands of families have been split apart, including families who have loved ones who are ill and are not able to see them in their final hours. I'm sure there are more cases like this." Catherine Garcia