The two nations appear eager to avoid an escalation in their tit-for-tat, with President Donald Trump signaling he has no interest in more violence following a casualty-free strike on U.S. forces — which Iran said “concluded” its response to Gen. Qassem Soleimani’s killing. But in a White House address yesterday, Trump said he’d tighten sanctions on Tehran, and U.S. forces in the region remain on high alert.

What about Iranian-backed militias? While Iraqi-based Kataeb Hezbollah urged restraint, another group called for revenge for a militant leader killed alongside Soleimani.

Read this OZY op-ed about why U.S. foreign policy is drifting dangerously.

As speculation swirls over yesterday’s Ukraine International Airlines crash near Iran’s capital, which killed all 176 people aboard, few believe the investigation will go smoothly. Iranian officials — who aren’t giving up the Boeing 737-800’s black box — deny the plane was shot down, but Ukrainian authorities say that’s one of the explanations they’re considering. Meanwhile, U.S. sources say neither Boeing nor the National Transportation Safety Board will be allowed to investigate.

How do such probes work? International aviation rules say the country in which the crash occurred is responsible for investigating, with help from the plane manufacturer and the airline’s country of origin.

The Duke and Duchess of Sussex have reportedly left Buckingham Palace “blindsided” by announcing they’ll ditch their senior roles in the royal family and become financially independent. The move, which follows months of reports that the couple was uneasy with public life, is aimed at “providing our family with the space to focus on the next chapter.” They’ll also adopt a new media strategy by engaging with less established journalists and organizations.

Why does it matter? Observers say the announcement could foreshadow a pared-down British monarchy — or presage the couple’s total exit from the royal family.

“It was as if I’d died.” That’s how the embattled ex-Nissan chief described his life in Tokyo before he jumped bail last week for Lebanon. In his first public appearance since fleeing, Ghosn vigorously defended himself against financial misconduct charges and blamed Japanese authorities for plotting his prosecution. But while the 65-year-old took responsibility for planning his escape from Japan, he shied away from divulging any details.

What’s next? Ghosn said he’s willing to face charges anywhere he can be “guaranteed a fair trial,” while the nature of his presentation yesterday suggests there are more media appearances to come.

Senate Majority Leader Mitch McConnell has excluded the possibility of “haggling” with Democrats over the rules of President Trump’s impeachment trial. China’s Commerce Ministry says Vice Premier Liu He will sign a “Phase 1” trade deal with the U.S. next week. And in response to speculation that he has a drug problem, Justin Bieber revealed that he’s been battling Lyme disease.

#OZYfact: Three-quarters of young teens seeking information online about depression said they were looking for personal anecdotes from people who had suffered in the past. Read more on OZY.

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In the run-up to Saturday’s presidential election in Taiwan, Hong Kong’s crisis has allowed the self-ruled territory to flaunt its democratic credentials, OZY reports. Taiwan clocked a 21 percent increase in Hongkongers applying for residency there last year, while President Tsai Ing-wen — widely expected to win a second term — is considering granting them asylum on humanitarian grounds. But that would require a new immigration law that locals fear could welcome Chinese spies.

How friendly are the two territories? Taiwan has no official position on Hong Kong’s protest movement, but community groups and churches have been sending supplies and support.

More changes are coming to Twitter — specifically, a way for users to limit replies to their tweets. The social media giant announced Wednesday that there will be four options for replies: They can be open to anyone, restricted to only a user’s followers, limited to just users tagged in the tweet, or blocked completely. The change will go into effect later this year after a test period.

What could go wrong? Some worry the feature could help public figures and politicians shield themselves from criticism.

Check out this OZY story about why Japan loves Twitter more than Facebook.

Some 800 scientific papers will be retracted after a “bombshell” report this week from the Russian Academy of Sciences revealed extensive unethical practices like plagiarism and gift authorship. It’s unclear if that will fix a longstanding problem, though: A 2018 investigation found nearly 4,000 cases of plagiarism across 1,500 journals. And a more recent survey concluded at least 70,000 papers in a sample of 4.3 million had been published at least twice — some up to 17 times.

Why the staggering numbers? Russian authors, apparently comfortable with lower standards, publish in domestic journals far more frequently than scholars in other countries, experts say.

For the second consecutive year, Hollywood’s biggest awards show will go on without a host, ABC chief Karey Burke announced yesterday. Last year, the Academy of Motion Picture Arts and Sciences dropped comedian Kevin Hart after decade-old homophobic tweets resurfaced. Without citing any specific reason for this year’s decision, Burke said she expects the Feb. 9 ceremony to be “a very entertaining show.”

Is it a winning strategy? Fewer than 30 million viewers tuned in last year — the second-smallest audience ever — though that was a 12 percent jump from 2018, reversing a four-year slide.

Read OZY’s Special Briefing on whether Netflix can keep its Oscars dreams alive.

Even single-player triple-doubles are rare — which is what made last night’s matchup between the Houston Rockets and Atlanta Hawks so special. Rockets guard James Harden posted 41 points, 10 rebounds and 10 assists, while his Hawks counterpart, Trae Young, put up 42 points, 13 rebounds and 10 assists during Houston’s 122-115 victory. It was the NBA’s first game featuring two 40-point triple-doubles.

How do the two players compare? While Harden, the league’s leading scorer, has posted 15 40-point triple-doubles in his career, Young’s was the first in Hawks history.