He is the author of the book Winning the Un-War: A New Strategy for the War on Terrorism, co-author of The Search for WMD: Non-Proliferation, Intelligence and Pre-emption in the New Security Environment, and co-author of Exiting Iraq: Why the U.S. Must End the Military Occupation and Renew the War against Al Qaeda. Peña is currently an analyst for MSNBC television and has been an analyst for Global TV (Canada) and Channel One News (a PRIMEDIA Inc. company) during the Iraq war.

He was previously the Director of Defense Policy Studies at the Cato Institute and has over 20 years experience as a defense policy and program expert, and senior manager—including work for a variety of government clients, including the Office of the Secretary of Defense, Program Analysis & Evaluation, Ballistic Missile Defense Organization (formerly the Strategic Defense Initiative Organization), Joint Chiefs of Staff, Defense Advanced Research Projects Agency, Defense Threat Reduction Agency, Air Force, Army, Navy, Department of Homeland Security, and Federal Emergency Management Agency. Peña has appeared on “Hardball with Chris Matthews” on MSNBC, “The O’Reilly Factor” on Fox News, “News Night with Aaron Brown” on CNN, the “McLaughlin Group” on PBS, and the BBC. He has also appeared on NPR’s “Public Interest,” “To the Point,” “Morning Edition”, and “The Diane Rehm Show” and “The Radio Factor” with Bill O’Reilly.

His articles have appeared in the New York Times, Washington Post, USA Today, Wall Street Journal, Los Angeles Times, Chicago Tribune, Chicago Sun-Times, San Francisco Chronicle, Houston Chronicle, Philadelphia Inquirer, Boston Globe, Atlanta Journal-Constitution, San Diego Union-Tribune, Orange County Register, Sacramento Bee, St Louis Post-Dispatch, Orlando Sentinel, Newark Star-Ledger, Hartford Courant, Washington Times, Associated Press, Reuters, Christian Science Monitor, Investors Business Daily, Bloomberg News, Defense News, Defense Week, Space News, Aviation Week & Space Technology, Financial Times (UK), Agence France Presse (France), The Globe and Mail (Canada), and The Guardian (UK). Peña received his M.A. in Security Policy Studies from the George Washington University and has a B.A. in Political Science from Claremont Men’s College.