The fallout over Seattle rapper Macklemore’s anti-Semitic costume at a Friday Experience Music Project event throws light on a cultural menace. The star, who said his “Elders of Zion”-style getup was picked at random, is both sweetly naïve and historically tone deaf.

“The character I dressed up as on Friday had no intended cultural identity or background,” Macklemore said in a statement. “A ‘Jewish stereotype’ never crossed my mind.”

America’s culture of celebrity magnifies all-things-boneheaded and inspired. Macklemore has been an outspoken advocate of same-sex marriage and a critic of rap’s misogynistic undercurrent. But intent is immaterial when the headline-grabbing outcome reinforces a degrading stereotype.

The best way to defang racial, gender and religious discrimination is to dissect it. Understand the history, the use of fear and lesser-than tropes, and it loses its kick. To achieve something beyond how to use politically correct terminology requires a candid public conversation. And “Northwest nice” is the enemy of candid dialogue.

For many, the impulse is to declare victory over human nature, to pretend that the progressive Northwest is a post-racial, post-sectarian society. That stifles the very conversations and education that can ameliorate prejudice.

Macklemore was born 15 years after the Seattle City Council overturned housing discrimination in 1968. As University of Washington History Professor Jim Gregory observed on KUOW Wednesday, restrictive covenants on Seattle homes, while invalid, are still part of property records. No selling of homes built in the 1920s through the 40s to “Hebrews” or Asians or “Ethiopians.” That legacy of discrimination lives on in nearly all-white north-end neighborhoods. The local chapter of the Anti-Defamation League famously challenged the anti-Semitic policies of the Laurelhurst Beach Club near the UW, finally winning in 1956.

The Fascists Silver Shirts, founded by a rabid anti-Semite, William Dudley Pelley, had a strong following on Whidbey Island and Snohomish County in the 1930s. Later incarnations include the posse comitatus and militia movement of the 1990s.

As last week’s ADL’s Global100 Survey documents, 1.09 billion (!) people harbor anti-Semitic attitudes. In the United States, 31 percent of respondents believe Jews are more loyal to Israel than to the U.S. Eighteen percent believe “Jews have too much power in the business world.”

Northwesterners, the patina of nice notwithstanding, need to talk openly about stereotypes. This is a teachable moment. It should be ongoing.