Trump has made it kosher for anti-Semitism to reenter the American mainstream | Trudy Rubin

This year marks the 60^th anniversary of the bombing of the Jewish Community Center in Nashville.  Fortunately, no one was hurt, but my sister-in-law, whose father was a local rabbi, remembers a rock being thrown through her living-room window.

So I know that anti-Semitism didn't arrive in America with the massacre in the Tree of Life synagogue in Pittsburgh.  Jewish refugees were denied entry to America during the Holocaust, and Jews were refused entry to clubs, hotels, and top universities until the 1960s.

Parochial-school kids, prepped by their priests, used to throw stones at me on my way home from elementary school and call me a "Christ killer." But I didn't mind, because I never felt threatened.  I am the product of an American era during which Jews gained entry everywhere. I thought overt anti-Semitism was passe in this country.

>> READ MORE: After the Pittsburgh shooting, I feel more Jewish than ever before | Perspective

I was wrong.  Donald Trump has made it kosher for anti-Semitism to reenter the mainstream.

There has been a 57 percent increase in anti-Semitic acts in the United States in 2017 over 2016, according to the Anti-Defamation League. The Pittsburgh shooting was the deadliest crime against Jews in American history.

Abe Foxman, the longtime former head of the Anti-Defamation League, explains it, in an interview with the Times of Israel: Since the Holocaust, America gradually built a "containment wall" against anti-Semitism, making it unacceptable to act on such ugly prejudice.  With his rants against Mexicans, immigrants, Muslims, the media, and liberal opponents, President Trump "broke down all the taboos" against attacking ethnicity, race, or religion.

The president's encouragement of mayhem at his rallies, his attacks on media as "the true enemy of the people" are an incitement to violence.  Alleged pipe bomber and Trump supporter Cesar Sayoc is believed to have chosen targets – such as President Obama, Hillary Clinton, George Soros, CNN — that were all denounced by the president.  Repeatedly.

With his dog whistles and conspiracy theories, Trump has helped anti-Semitic tropes reenter the national conversation, magnified by Fox commentators and alt-right websites he favors. Even the mainstream media feeds the process when we report on his inflammatory tweets.

>> READ MORE: Our descent into vitriol began long before Trump – and Democrats are culpable too | Marc Thiessen

The president is enamored of dog whistles — buzzwords that make anti-Semites happy.  He slams "globalists" and "the eastern elite" and Jewish financial leaders he dislikes, such as Soros, and former Fed head Janet Yellen, while extolling "nationalists."

To bigots, nationalist means white, and globalist means nefarious Jewish plotters.  Prime example: Trump encourages the demonization of Soros, whom the alt-right portrays as a mastermind out to destroy the white Christian world.

During the 2016 campaign the president refused to criticize David Duke, the infamous Ku Klux Klan leader. "I know nothing about David Duke [or] white supremacists," Trump piously insisted.  Duke praised his support.

Similarly in Charlottesville, the president claimed there were "good people on both sides." Among those people in Charlottesville were neo-Nazis who marched with torches and chanted,  "Jews will not replace us."

"He didn't give them the brownshirts," says Foxman. "But he emboldened them.  And when he had an opportunity to put [them] down, he didn't.  I consider that a greater sin."

So where do the bigots go with their legitimization by the leader of the free world? "They look for a moment. … They need a flash point," says Foxman.

The perfect example is Robert Bowers, the man charged in the Pittsburgh killings, whose online postings show a hatred of Jews. He wasn't pro-Trump, but he glommed on to the president's false claims that a "caravan" of Central Americans was "invading" our country aided by Soros' funding.  Somehow Bowers linked all this to the Hebrew Immigrant Aid Service (HIAS), which does noble work helping refugees but has nothing to do with the so-called caravan.

>> READ MORE: After Pittsburgh synagogue shooting, clients ask HIAS PA: 'Am I safe?' | Mike Newall

"Here for Bowers were the Jews, celebrating bringing in these invaders," says Foxman. "It was that flash point."

Of course, Trump insists he can't be an anti-Semite since his daughter and son-in-law are Jewish. That only makes what he is doing even more disgusting — fueling anti-Semitism just to keep the votes of the bigots in his base.

The president made that point clear after the massacre.  After first blaming the Jews (they should have had armed guards at the synagogue, he said), he briefly denounced the "anti-Semitic" murders and visited Pittsburgh.  But he quickly reverted to campaign mode, lamenting that news coverage of the pipe bombs and massacre had slowed the GOP's campaign momentum.

Trump blew the chance to put a brake on the rise of the new anti-Semitism.  He could have imitated Ronald Reagan, who showed zero tolerance when anti-Semitism began to infect the GOP in the mid-1980s.  Reagan pushed through a GOP platform resolution that disassociated the Republican Party "from all people and groups who practice bigotry in any form."

But this president shows no interest in denouncing the white supremacist groups and conspiratorial websites that support him.  That might hinder his vote tallies.

With Trump's help (and the enabling of Jared, Ivanka, and GOP leaders) the anti-Semitism of my parents' era is clawing its way toward the new normal.  We will have to fight hard to shove it back under the rocks.