Beginning in 2012, Rosenberg covered national elections in the U.S. and Israel, and his work on these and other subjects appeared in The New York Times, Washington Post, The Atlantic, The Guardian, and the Wall Street Journal, among other outlets.

[2] Until 2021, he was a senior writer at Tablet magazine, where he tackled topics ranging from American Jewish responses to modern critical scholarship of the Bible,[3] to contemporary Islamophobia,[4][5][6] to the forgotten history of Mormon-Jewish relations.

In November 2021, he moved to The Atlantic, and launched a newsletter called Deep Shtetl,[20] where he continued his coverage of politics, culture, antisemitism, and social media dynamics, including an exploration of how a Jewish character came to be on the cult classic sci-fi show Firefly,[21] the story behind the Hanukkah menorah used by Vice President Kamala Harris,[22] interviews with celebrated Jewish authors and artists like Dara Horn[23] and Ben Platt,[24] a profile of Israeli prime minister Yair Lapid,[25] and a deep dive into Albert Einstein's little-known 20-year friendship with Orthodox rabbi Chaim Tchernowitz.

"[46] Since the report's publication, Rosenberg has focused extensively on the issue of online harassment and antisemitism,[47] including through the creation of the "Impostor Buster" Twitter bot that exposed neo-Nazi trolls masquerading as minorities on the platform,[48] which received coverage from The New York Times and other global news outlets.

[56][57][58] "Rosenberg is not the only musically inclined member of his family," reported Jewish Insider,[59] "his grandfather was a Hasidic composer who, as a young man, escaped Nazi Europe with the assistance of Japanese diplomat Chiune Sugihara, who issued him a visa."