BERLIN (WASHINGTON POST) - Protests against Israel, sparked by President Donald Trump's decision to recognise Jerusalem as its capital, are once again forcing Germany to weigh the value of free speech against the burden of its Nazi past.

Pro-Palestinian demonstrators have been burning Israeli flags in the centre of Berlin while chanting anti-Semitic slogans threatening violence against Israelis. One protest on Friday took place only 100 yards from the city's sombre Memorial to the Murdered Jews of Europe, a reminder of Germany's responsibility for the worst mass murder in history.

A few thousand protesters have taken part so far. Except for several arrests, German authorities have generally refrained from interfering, even as top officials said they were "ashamed" by "the evil face" of anti-Semitism on display.

But Ms Deidre Berger, the director of the American Jewish Committee in Berlin, said she believes that flag burning can incite violence against Jews and that Germany's response does not adequately deter such anti-Semitism.

"Of course, freedom of expression needs to be respected - but if in the heart of Berlin flags (with the Star of David) are being burned, surely the police should intervene. It's incitement even if it may not be a direct violation of existing law," Ms Berger said.

She argues, further, that Berlin authorities should hire more Arabic translators to monitor protest speeches.

That raises another difficult issue: Although anti-Semitism is not hard to find among German right-wingers, the protests have sparked concerns among some politicians and Jewish associations that Germany may be failing at preventing the proliferation of prejudices, especially among refugees.

What, in other words, should Germany do about the attitudes of Middle Eastern immigrants who don't share a sense of responsibility for the Holocaust?

In a speech on Friday, German President Frank-Walter Steinmeier reminded refugees and other migrants of the need for tolerance in a country that shoulders such a historical burden.

"This responsibility does not recognise caveats for migrant backgrounds and no exceptions for newcomers," Mr Steinmeier said.

A recent survey commissioned by AJC Berlin found "widespread anti-Semitism" among refugees.

Officials have also expressed concerns over the influence of the Turkish government on the almost two million German Turks, even though many of them have lived here for decades, especially after President Recep Tayyip Erdogan called the recognition of Jerusalem a "red line" for the Muslim world and threatened last week to cut ties with Israel.

Research conducted by AJC Berlin has found that educational factors may have contributed to recent escalations at anti-Israel protests, too.

Some teachers here, Ms Berger said, were reluctant to discuss Israel and anti-Semitism in classes with a disproportionate share of second- or third-generation migrants, fearing a student backlash.

Anti-Semitic crimes here have slightly increased since the 2015 influx of refugees into the country, even though right-wing extremists are still responsible in the vast majority of cases.

Far-right Alternative for Germany (AfD) politician Björn Höcke provoked outrage when he called Berlin's Holocaust memorial a "memorial of shame", and other members of the party have also recently been accused of fueling hatred.

Flag burnings as a sign of protest may be common elsewhere, but they are seen as especially problematic in Germany.

The country has had strict hate-speech laws since the end of World War II; it is illegal, for example, to deny the Holocaust. At the same time, Germany since 1945 has fully committed itself to democratic values, including, within limits, freedom of speech.

Burning a country's flag is only a crime in Germany if it's an official banner - for instance, if it belongs to an embassy. If flags were bought privately or made by the protesters themselves, authorities are unable to intervene under existing laws unless they specifically prohibited the burning of items in advance of a protest.

Germans are debating whether the burning of the Israeli flag is inherently anti-Semitic, and whether Germany's existing laws against hate speech allow anti-Israel extremists too much leeway.

Protest organisers have in the past defended the burning of Israeli flags as being directed against the country's politics, and not against Jews in general.

Lawmakers from various parties are nonetheless demanding tougher measures.

"It is Germany's task to protect Israel. We are obliged to guarantee that Holocaust survivors have at least one place they can always go," Foreign Minister Sigmar Gabriel, a Social Democrat, said on Dec 14.

"We have been watching this unfold for too long already," Mr Jens Spahn, a senior member of Chancellor Angela Merkel's Christian Democratic Union, who supports tougher laws, told the newspaper Die Welt.

However, some Social Democrats and members of other parties say that existing laws need to be enforced but not changed, and emphasise the importance of upholding free speech.

Opponents of tougher laws argue that authorities already have the means to stop the escalation of protests.

After officials explicitly banned the burning of flags at a demonstration in front of Berlin's central railway station last week, protesters refrained from doing so even as they continued to voice strong attacks against Israel.

In a video of the event, an unnamed speaker can be heard saying into a microphone as hundreds listened: "We are here on the streets to protest against the occupying power Israel, which should disappear once and for all."

Ms Berger, of the AJC, emphasised that longer-term approaches apart from tougher protest laws are needed.

"We've heard again and again that anti-Semitism won't be tolerated - but what really matters are actions," said Mr Levi Salomon, spokesman for Berlin's Jewish Forum.