Remember the tree that fell in the forest, causing a ruckus of breaking branches and cracking trunks as it crashed? According to the fortune-cookie school of philosophy that popularized this conundrum, there would be no noise, or no verifiable noise, if there were no human being around to witness it ... unless, I would hasten to add, the human witness on hand happened to be a journalist.

With a journalist -- or, rather, with a press corps -- you never know what reverberations an event or revelation will generate. And I'm not even thinking of the big media silence on the so-called "Feith Memo." Tossed out many news cycles ago by the Weekly Standard in the form of a big, fat scoop, this top-secret U.S. government memo offers intelligence, in 50 numbered points, on the operational relationship it says has existed between Osama bin Laden and Saddam Hussein since the early 1990s. The Standard called its article "Case Closed," but that doesn't mean the press shouldn't even take a peak.

This time, it's another Big Story that has been reliably launched only to sink with little trace. It concerns the resurgence of anti-Semitism in Europe, and it broke in the Financial Times on Nov. 21. "The European Union's racism watchdog has shelved a report on anti-Semitism," the newspaper reported, "because the study concluded Muslims and pro-Palestinian groups were behind many of the incidents it examined."

This suppression is a disgrace. Having commissioned the report during a shocking European upsurge in anti-Semitic violence in 2002, the EU has now buried the report during another shocking European upsurge in anti-Semitic violence in 2003. Indeed, the Financial Times published its initial story the same week that two Jewish synagogues in Turkey were devastated by Islamic bombers, and a Jewish school near Paris was firebombed. A French-language news Web site, www.revue-politique.com, now reports that the brutal murder of a Jewish DJ in Paris on Nov. 19 may have been an act of Muslim anti-Semitism.

According to the Financial Times, the EU racism commission (EUMC) was appalled by the report's conclusion that the new anti-Semitism is largely a phenomenon of the 21st-century left and the Islamic movement in Europe. As Juliane Wetzel of the Berlin research center that completed the research told the newspaper in a follow-up story, "The study put the EUMC in a difficult situation because it singled out the group (young Muslims), which they (the EUMC) seek to protect. They refused to publish it because it clashed with political correctness."

Refusing to publish the report is an embarrassment that exposes the lengths to which European bureaucrats will go to suppress a terrible truth to sustain a dangerous fantasy -- namely, that anti-Semitism is the sole province of jackbooted rightists swilling beer and sieging heil. But the bureaucrats have been thwarted. Their story is out. Juicy details abound -- as in the fact that the same EU racism commission has already brought out three reports on anti-Islamic attitudes in Europe in the two years since 9/11. But practically no media organization in Europe or the United States has yet to take up the cry.

Such journalistic silence does more than deprive us of information. It sucks the oxygen from the free exchange of ideas, stifling debate before it occurs. This undermines more than the state of the press. It adversely affects public discourse everywhere, lending credence to the pernicious notion that subjects of grave importance -- Muslim anti-Semitism and European denial, for example -- must be consigned to furtive whispers, if they are mentioned at all.

This same silence leads to a tyranny of political correctness, as evidenced by author Robert Spencer's recent experience. His 2002 book, "Islam Unveiled" (Encounter, 2002) (read review), a carefully researched analysis of the disturbing links between Koranic teachings and Islamic terrorism, was slated for publication in France this month. Death threats against both the book's translator, French writer Guy Milliere, and its French publisher, Yves Michalon, have frightened the publishing house into canceling the book. ("It's ironic," Mr. Spencer said in an interview with www.frontpagemag.com . "If you don't say Islam is a religion of peace, they will kill you.") Before shouting vive la France avec irony, it's worth noting that author Ibn Warraq has heard from U.S. publishing sources that similar fears have prevented an American reprint of his excellent 1995 book, "Why I Am Not a Muslim."

Hiding facts and suppressing arguments -- not publishing them, not airing them, not facing them -- doesn't make them go away. It chokes the free flow of ideas our democracies require to survive.