A memorial of flowers and stars line the sidewalk outside Tree of Life synagogue in Pittsburgh on Sunday. (Gene J. Puskar/AP)

The dynamite erupted inside the Hebrew Benevolent Congregation at 3:38 a.m. on Oct. 12, 1958.

Within minutes, the perpetrator phoned a newspaper reporter to promise it would be “the last empty building in Atlanta that we will bomb,” declaring all Jews and black people to be “aliens.”

It was the seventh time in less than a year that a synagogue in the South had been bombed or had been the target of an attempted bombing.

But it was only the first time President Dwight D. Eisenhower publicly condemned one of them.

At a cornerstone-laying ceremony at a Protestant church in New York that morning, Eisenhower ordered the FBI to immediately assist local police in the investigation, which, unlike in the other bombings, led to the arrest of five suspects within days. He said he believed “we would all share in the feeling of horror, that any brigand would want to desecrate the holy place of any religion, be it a chapel, a cathedral, a mosque, a church or a synagogue."

Many, including the Rev. Martin Luther King Jr., celebrated his actions. Others asked another question: What took so long?

“Perhaps the country might have been spared much of this present nightmare if he had been able to find his voice — and his FBI reports — when the explosions began many months ago,” read one New York Post article titled, “Ike and the Southern Terrorists.”

It’s just one demonstration of how what a president says, or doesn’t say, in response to anti-Semitism can have direct or perceived consequences. And it’s the very conflict President Trump is now facing as he swats at criticism that his divisive rhetoric has stoked anti-Semitism, and that, in the eyes of some, his response to Saturday’s mass shooting at Pittsburgh’s Tree of Life synagogue has been unsatisfactory. Trump condemned the “scourge of anti-Semitism” that “cannot be ignored, cannot be tolerated and cannot be allowed to continue.” But as The Washington Post’s David Nakamura reported Saturday, critics have charged that he’s repeatedly fostered nativist impulses among his base since the time he announced his run for office and called Mexicans “rapists.”

In a tweet Sunday, Trump lashed out at the news media for reporting on these criticisms. “The Fake News is doing everything in their power to blame Republicans, Conservatives and me for the division and hatred that has been going on for so long in our Country,” he tweeted. “Actually, it is their Fake & Dishonest reporting which is causing problems far greater than they understand!”

American presidents have been combating anti-Semitism, or failing to do so, since the nation’s founding, with at least one managing to do both at once.

Some of the nation’s earliest presidents, the original champions of freedom of religion, were the Jews' closest allies. George Washington, for example, wrote to a Jewish congregation in Rhode Island in 1790 that it could expect to find tolerance and protection from the federal government despite the state’s refusal to grant them full rights as citizens to vote or hold office, signaling the federal government’s commitment to religious liberty.

“May the children of the stock of Abraham who dwell in this land continue to merit and enjoy the good will of the other inhabitants,” Washington wrote, “while every one shall sit in safety under his own vine and fig tree and there shall be none to make him afraid."

Abraham Lincoln was famously friendly with the Jews, a relationship the Jewish publication Mosaic described as “unusual” for its genuine intimacy. Most notably, Lincoln condemned anti-Semitism within his own army during the Civil War. In 1862, Union Gen. Ulysses S. Grant ordered the expulsion of all Jews from parts of Kentucky, Tennessee and Mississippi regarding his generalized suspicions that they were responsible for the black market cotton trade. Lincoln, upon word from outraged Jews, immediately revoked the order. “I do not like to hear a class or nationality condemned on account of a few sinners,” he said.

But some presidents in the 20th century, such as Presidents Franklin D. Roosevelt and Richard Nixon, exhibited some degree of alleged anti-Semitism, at least behind closed doors.

In Roosevelt’s case, he publicly decried bigotry and violence against the Jews, but private statements about Jews, as well as his administration’s restrictive immigration policies limiting Jewish immigration and refugees, have sullied his legacy in the eyes of some historians.

In a 1943 conversation with a resident general in Morocco for example, the general complained about Jews, and Roosevelt sympathized, archived meeting minutes show. Roosevelt proposed that Jews' participation in professions such as law and medicine should be “definitely limited” to “further eliminate the specific and understandable complaints which the Germans bore towards the Jews in Germany.”

In Nixon’s case, tapes in 1999 revealed him expressing a similar sentiment while lashing out against Jews in Oval Office phone conversations. He lamented that “the Jews are all over the government” and that there should be fewer in key government positions.

“Generally speaking, you can’t trust the bastards,” he said in one conversation with his chief of staff, H.R. Haldeman. “They turn on you. Am I wrong or right?” Haldeman said he was right.

President Trump has staunchly denied that his rhetoric has in any way sowed division or contributed to anti-Semitism. He has said he’s planning a trip to Pittsburgh in the wake of the attack. But by early Monday, more than 16,000 people had signed a letter written by 11 leaders of the Pittsburgh affiliate of Bend the Arc, a national organization for progressive Jews, that said Trump is not welcome in Pittsburgh until he denounces white nationalism and stops “targeting” minorities.

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