Lately it's been impossible to miss.

In Warsaw and Brussels, deep in primeval forests and overlooking the soccer pitch, the bad blood between the Polish government and the European Union officials appears to be seeping into just about every evident interaction — and as European Council President Donald Tusk observed Thursday, it's threatening to rend their relationship apart.

"There is a question mark over Poland's European future today," Tusk told reporters outside a prosecutor's office in Warsaw, where the former Polish prime minister was grilled for hours about the 2010 plane crash that killed 96 people, including the country's president at the time, Lech Kaczynski.

Kaczynski's twin brother, Jaroslaw, now happens to be the most powerful man in Poland. At the head of the conservative Law and Justice party, which holds nationalist views and a deep skepticism toward the European project, Jaroslaw Kaczynski has led the country far to the right and farther from the strictures of the EU, where his domestic rival Tusk holds the reins.

Late last month alone, Poland defied several commandments from Brussels, plowing ahead with its logging program in the Bialowieza Forest despite an injunction and pursuing controversial reforms that would place its judiciary squarely under presidential control. Those reforms, which Tusk criticized as likely to create a "black scenario," made it all the way to the Polish president's desk.

President Andrzej Duda, a member of Kaczynski's party, surprised onlookers by vetoing two of the bills — but signed the third, which reorganized the judiciary on a local level. That wasn't good enough for the EU, which launched punitive measures against the country just days later.

"It smells like an introduction to an announcement that Poland does not need the European Union and that Poland is not needed for the EU," Tusk said Thursday of increasing disputes between the organization and its member state. "I am afraid we are closer to that moment."

For Tusk and Kaczynski, that friction is not simply geopolitical; for years it has been personal, too.

Kaczynski has long held Tusk and his center-left government, which held power in Poland from 2007 to 2014, morally responsible for the tragic death of his twin and the failures of the investigation afterward, The Guardian reports. Hence Tusk's presence in Warsaw on Thursday: Kaczynski's party took control of the prosecutor's office in 2015, pledging to re-investigate the plane crash and its aftermath, including Tusk's alleged negligence.

Tusk's lawyer, for his part, dismissed Thursday's hearing as politically motivated.

Still, the mounting animus has owed to more than the conflict of two men — more, even, than just the events of recent months. Many Poles have lately harked back much further, to the violence of World War II.

The "Polish government is preparing itself for a historical counteroffensive," Kaczynski said last week, according to The Associated Press. He and other Polish lawmakers have renewed calls for war reparations from Germany, which today is the centerpiece of the EU but decades ago represented the Nazi invader that killed nearly 6 million Poles.

Germans must "pay back the terrible debt they owe to the Polish people," said Polish Defense Minister Antoni Macierewicz. He reasons that Poland's 1953 decision to waive its right to financial reparations — "in the spirit of democracy and peace," notes the German publication Deutsche Welle — is invalid because Poland was at that time no more than a "Soviet puppet state."

"If Jews have gotten compensation — and rightly so — for loss of property, why shouldn't we too make claims?" one Law and Justice party lawmaker said.

And those bitter feelings are not confined simply to the halls of power.

UEFA, the governing body of Europe's premier international soccer tournament, disciplined the Polish club Legia Warsaw on Friday after its fans raised a vast banner commemorating Polish victims of the Nazi invasion at a recent match.

"During the Warsaw Uprising Germans killed 160,000 people," the banner read, according to an AP translation. "Thousands of them were children."

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