Secretary of State John Kerry’s brother took the unusual step today of writing an op-ed defending him against accusations by some Israeli politicians of being anti-Semitic.

Cameron Kerry, who converted to Judaism, wrote in the Israeli newspaper Yediot Ahronoth that “such charges would be ridiculous if they weren’t so vile.”

John Kerry’s focus on Middle East peace talks was condemned publicly by at least one member of Israel’s Knesset as containing “anti-Semitic undertones,” and he has also been criticized by others, including the Israeli defense minister, for taking a “messianic” and “naïve” approach to talks.

In his brother’s op-ed, which appears in today’s edition of the Hebrew-language newspaper and is translated into English on the U.S. Embassy in Tel Aviv’s Facebook page, Cameron Kerry details their ancestors’ own experience with anti-Semitism. He noted that their grandfather, Frederick Kerry, was born Fritz Kohn in Czechoslovakia and, upon emigrating to America and joining the military changed his name and converted to Catholicism because of anti-Semitism in the ranks.

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