Alexander is host of The Open Mind on PBS. He has covered American politics, civic life and Millennials since the 2008 presidential campaign. His work has been profiled in The Washington Post, New York Times, Los Angeles Times, Des Moines RegisterChristian Science Monitor, VarietyMedium, and on NBC NewsMSNBCC-SPANNPRCNN, BBC and ABC, among other media outlets.

His writing has appeared in TIME, USA TODAY, Daily BeastReutersRealClearPolitics, NYT's Room for DebateThe Wall Street Journal, Boston Globe and Philadelphia Inquirer, among other publications. He is coauthor of A Documentary History of the United States (Penguin, 2018)

He has lectured at the NewseumNational Constitution CenterMuseum of American FinanceFDR Library and MuseumPost-Truth Initiative at University of Sydney, Center for Information and Bubble Studies at University of Copenhagen, Institute of Applied Politics at University of Akron, Center for Telecommunication and Law at Michigan State, Clemson, Sewanee, Franklin Pierce, Carroll and Skidmore College, among other institutions of learning. He was the political director for WHRB 95.3 FM and host of The Political Arena.

A native New Yorker, he is a graduate of Phillips Academy in Andover, Massachusetts and Harvard.