Tombs are clustered in the Jewish cemetery in Krakow. The government has participated in efforts to preserve Poland’s Jewish heritage, notably cemeteries, but community leaders say its recent public statements have taken a toll. (SOPA Images/LightRocket via Getty Images)

On any given Friday night, the only synagogue in this city to survive the Holocaust draws enough worshipers for a minyan, the obligatory quorum of 10 Jewish adults. Not too long ago, Rabbi Michael Schudrich said, that would have been unthinkable.

On the eve of World War II, Warsaw was home to Europe’s largest Jewish community. But the liquidation of Polish Jewry during the Holocaust, followed by an anti-Semitic campaign that drove thousands of Jews from the country in 1968, meant that for decades the community existed mostly as a fading memory. Very few Jews were left, and some never told their children they were Jews. In recent years, though, and against all odds, Jewish life has revived in Poland.

Now a new threat has emerged, putting that fragile and hard-won progress in jeopardy. The government’s “Holocaust law,” criminalizing any suggestion that Polish citizens participated in Nazi atrocities, is due to go into effect around the beginning of March, and Jewish leaders say it has already provoked an eruption of prejudice.

For some, the parallels with the rhetoric of March 1968, when Poland’s communist government used anti-Semitism to shore up nationalist support, are hard to ignore.

At the recent Munich Security Conference, Poland’s prime minister, Mateusz Morawiecki, called for an “open debate” about the Holocaust and declared that “there were Jewish perpetrators.” His comment came days after a Polish presidential adviser, Andrzej Zybertowicz, said that Israel’s outrage about the new law derived from a “feeling of shame at the passivity of Jews during the Holocaust.”

The chief rabbi of Poland, Michael Schudrich, prays during a ceremony in March 2016 at the burial site of Jewish Holocaust victims near the village of Jagiella. Later, a ceremony was held to honor a Polish family killed for sheltering the Jews. (WOJTEK RADWANSKI/AFP/Getty Images)

In addition to a law policing Holocaust speech, the government has also recently proposed another bill that would limit kosher and halal slaughter.

“In everything that’s happened in the last two years, there’s been a growing feeling of unease,” said Schudrich, the chief rabbi of Poland, referring to the general climate.

The period specified by Schudrich covers the rise of the right-wing Law and Justice party, which assumed control of the Polish presidency and Parliament in 2015 and has since attempted to rein in the judiciary and control local media. Although Schudrich acknowledges that the government has shown some interest in preserving Poland’s Jewish heritage, notably Jewish cemeteries, he says its recent public statements have taken their toll.

“For the first time, I hear people saying that maybe there’s no future for us in Poland,” he said. Schudrich arrived in Warsaw from the United States in 1990, a year after the fall of communism.

Many members of Poland’s Jewish community say they do not believe the Holocaust law was conceived with the explicit goal of antagonizing Jews. Instead, they contend, the government meant it as an olive branch to appease the ruling party’s fervently nationalist base and thus cement its hold on power.

Warsaw’s Nozyk Synagogue, shown in 2016, is the only Jewish house of prayer in the Polish capital to have survived the Holocaust. (Czarek Sokolowski/AP)

What has stung, though, is the government’s apparent refusal to denounce the wave of anti-Semitic threats that followed the legislation.

Anna Chipczynska, president of the Warsaw Jewish community, said that since the bill was proposed, Jewish organizations in Poland have been flooded with hate mail, and anti-Semitic attacks have exploded on social media.

“I don’t think this government wants to see anti-Semitism in the streets, but they don’t want to pay the political price to condemn it, either,” said Konstanty Gebert, a prominent Polish journalist who has been involved in Jewish causes here since before the fall of communism.

When pressed, Jaroslaw Kaczynski, the leader of the Law and Justice party, has condemned ­anti-Semitism — but only in the abstract, critics say. Neither he nor his allies stopped supporters at an Independence Day march in Warsaw in November from chanting: “Pure Poland, Jew-free Poland” and “Jews out of Poland,” among other slurs.

A similar demonstration occurred when President Andrzej Duda signed the new law this month, and again government officials said nothing substantive.

Chipczynska said she worries that people might hide their Jewish origins or refrain from exploring them, as many Polish Jews did during the communist period.

“They might see a stigma,” Chipczynska said. “And therefore there is a legitimate risk that people will hide and cover their identities, their backgrounds. It’s extremely concerning.”

Others, though, remain encouraged by the accomplishments and unlikely milestones reached in recent years.

Poland’s small but growing Jewish community now numbers approximately 10,000 — although the figure could be much higher, experts say, if all those with some Jewish heritage are taken into account.

Conservation efforts, often led by non-Jewish Poles, have salvaged what little remains of Yiddish culture in a place that was once part of the Pale of Settlement, the territory to which Jews were restricted for centuries. Among Poland’s biggest tourist destinations is the acclaimed Polin Museum of the History of Polish Jews, which was built on the site of the Warsaw Ghetto and opened in 2014.

“The revival is real, and it’s here to stay,” said Jonathan Ornstein, director of the Jewish Community Center of Krakow, which has grown so much it started a kindergarten last year. “Ultimately it comes from the people, and I really don’t think that general environment will go away.”

Barbara Kirshenblatt-Gimblett, chief curator of the Polin Museum in Warsaw and an emeritus professor at New York University, also attributed much of the community’s progress to the genuine interest of non-Jewish Poles.

“They have the feeling that something profoundly catastrophic and traumatic happened, and that it happened there,” she said in a telephone interview from New York. “However elusive that sense of something missing might be, there are those who have dedicated themselves to recovering the memory of what was lost and, in a sense, of confronting the catastrophe.”

Despite the recent uptick in anti-Semitic speech in Poland, Gebert said, life is still better here for Jews than in some other parts of Europe.

“We still haven’t had incidents of physical violence,” he said. “I walk around with a kippah,” or yarmulke, “and might get a nasty stare, but that’s it. Anyone in Paris with a kippah would be glad that’s all there is.”

Others find it harder to overlook the government’s indifference to what it has unleashed.

Said Schudrich: “I remain very optimistic, but I’m a great optimist with a broken heart.”

Magdalena Foremska in Warsaw contributed to this report.