Han’s rise to a professional career in Italy has been the most tangibly successful byproduct of the country’s effort. He played five games for Cagliari at the end of the 2016-17 season and scored his first Serie A goal on April 9. Mario Passetti, the general manager of Cagliari, said Han was signed through 2021, but he would not disclose the terms of the contract.

Like others with a stock in Han’s success, Passetti played down the importance of Han’s heritage.

“He is a really good kid who behaves and carries out a life like all young athletes entering the professional sports world, with friends away from the field and profiles on social media,” Passetti said in an email. “Nationality has never been a criterion that would determine the signing or not of a player.”

But some wonder if it should be.

The Skeptics

In May 2016, two members of the Italian Parliament’s Chamber of Deputies, Michele Nicoletti and Lia Quartapelle, initiated a formal request that the Italian government investigate the contract and the status of Choe Song-hyok, a North Korean product of I.S.M. Academy who had just signed with Fiorentina.

Their concerns, Nicoletti said in an interview, were twofold. First, they asked whether any transfer of money — at any point — had violated international sanctions banning payments to North Korea. Second, they wondered whether Choe’s human rights were being restricted in any way.

In 2014, a report commissioned by the United Nations Human Rights Council had unequivocally stated that a broad catalog of human rights was being egregiously violated by the North Korean government. Those abuses — including restrictions on personal liberties, strict state surveillance and the seizure of as much as 90 percent of an individual’s wages — often extended to an estimated 100,000 North Koreans working outside the country.

(That is why, in July, the United States’ secretary of state, Rex Tillerson, said that any country hosting North Korean workers was “aiding and abetting a dangerous regime.”)

Experts say North Korea has sent more workers abroad to fulfill an urgent need back home for hard currency. But in this context, a star athlete offers something unique: a potential vessel of soft power, a rarity for the North Korean government. Remco Breuker, a professor of Korean Studies at the University of Leiden in the Netherlands, said that if Han or another player were to achieve soccer stardom, “politically the payout would be huge” for North Korea.