Siegel worked at The New York Sun as an editorial writer and the paper's first op-ed page editor when it launched in 2002.
Siegel was editor-in-chief of the New York Press in 2005 and 2006, and worked as an editor at Politico from 2008-2010.
He has also worked in politics at times, working as a researcher for political consultant Hank Sheinkopf in 2001, and as policy director for New York State gubernatorial candidate Thomas Suozzi in 2006.
Siegel is co-author (with his father Fred Siegel) of The Prince of the City: Giuliani, New York and the Genius of American Life, which appeared on the 100 Notable Books of 2005 list compiled by The New York Times.
He has made guest appearances on CNN, MSNBC and National Public Radio.