Two European leaders came to Washington this week, partly to address a reality: The first step to handling disagreement over transatlantic relations is to learn to coexist. “It has been a learning curve,” says a former EU ambassador, “and rather a squiggly one.”

This next piece, too, is about roles and adaptation. In a calmer Iraq, political candidates are emerging from the ranks of the Shiite fighters who helped defeat ISIS. The question now, as they pitch new national unity: With only their military credentials, can they win over a people now concerned with bread-and-butter issues?

Who should be on the hook for making the American dream accessible? The announced end of a federal program that allowed the spouses of those holding special work visas to work, too, is raising questions about job equity and corporate practices – and pointing out the need to ensure that US-citizen workers also have fair access to opportunities.

Energy innovation isn’t braking for politics. Our reporter found that the aspiration of inventors, researchers, and entrepreneurs is alive and well – and so is some federal support that many of them see as indispensable.

History can be divisive, or it can be a source of unity. Often it’s both. In Congo, a country long splintered by civil strife, many hope that a new national museum could provide a social balm by emphasizing the shared history of the country’s hundreds of ethnic groups.

On Monday, the president of Nigeria, Muhammadu Buhari, will become the first African leader to meet President Trump at the White House. Much of the meeting will probably focus on what the United States can do for Nigeria. The continent’s largest economy has a median age of only 18, a sluggish economy, and endemic corruption.

Yet Mr. Buhari could have something to offer the US as well.

Nigeria may be one of the few countries willing to negotiate with a branch of Islamic State (ISIS), part of its decade-long struggle with jihadi groups such as Boko Haram. Most other nations, including the US, refuse to talk to ISIS or its affiliates.

On Feb. 19, militants from Islamic State in West Africa Province (ISWAP) seized 112 schoolgirls and one boy from the town of Dapchi in northeast Nigeria. A month later, after negotiations with the government, the group accepted a temporary cease-fire and released most of the children. The government said it paid no ransom. It is possible that ISIS leaders in the Middle East ordered the release.

Whatever the motive, the negotiations may represent a critical shift in how to deal with terrorists other than a strictly military approach. Under Buhari, Nigeria has beefed up its armed forces to counter Boko Haram and ISWAP. But it has also started to tackle corruption and improve the economy, especially in the largely Muslim northeast where the militants have found support.

Nigeria’s soft power against jihadis included the election of Buhari as president in 2015. He was the nation’s first candidate to defeat an incumbent president and achieve a peaceful handover of power from one party to another. Such democratic success stands out in Africa, which still struggles to remove long-ruling leaders who suppress opponents and tinker with constitutions and elections to stay in power.

As a former general, Buhari has improved the military’s capabilities against the insurgents. But he also relies on other tactics, such as an offer of amnesty to militants who surrender. “We are ready to rehabilitate and integrate such repentant members into the larger society,” he said.

Nigeria, with a highly diverse population of more than 180 million people, has far to go in improving its democracy, economy, and military. Yet it has shown leadership within Africa on many fronts, such as helping restore democracy in nearby Gambia. Perhaps it might also be a pioneer in how to talk with militant groups. As Mr. Trump prepares to talk to North Korea, a country he has designated as a state sponsor of terrorism, perhaps Buhari can offer some advice.