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My Coast Guard
Commentary | July 10, 2023

Message from Secretary Mayorkas on CWMD Transitions

By Alejandro N. Mayorkas, Secretary of Homeland Security 

I am pleased to announce that Ms. Mary Ellen Callahan will be appointed as the Assistant Secretary of the Department of Homeland Security’s Countering Weapons of Mass Destruction Office (CWMD).

Since September 2021, Ms. Callahan has served as Chief of Staff to Deputy Secretary John K. Tien, providing substantive policy advice to the Deputy Secretary on a wide range of domestic and international policy and operational issues.  Ms. Callahan was a key interlocutor and partner to Department Agency and Office leaders, interagency partners, the NSC, and the White House.  Ms. Callahan’s stewardship of the Department’s vital national security interests was critical to gains made in the National Operations Center, operations to counter-human smuggling, continuity of operations and government, and stemming maritime migration.   

Ms. Callahan previously served in the Department as the Chief Privacy Officer and Chief Freedom of Information Act Officer from March 2009 until August 2012.  In addition to her federal experience, Ms. Callahan served as Assistant General Counsel for Privacy and Cybersecurity at The Walt Disney Company and was a partner at two major international law firms.

Ms. Callahan’s tenacity and passion for the Department will translate seamlessly to leadership of the CWMD Office and its critical mission of protecting the homeland.  

On behalf of the Department, I thank Mr. Gary Rasicot for serving as the Acting Assistant Secretary for the past two years.  His steady leadership and expertise were instrumental in leading the Department through some of the toughest issues including COVID travel restrictions, protecting major events such as the Super Bowl and the Kentucky Derby, and building trust and confidence with our State, local, territorial, and tribal partners.  Under his leadership, CWMD made significant progress with State and local partners in biosurveillance and biodefense, enhancing national security in the event of bioincidents. Mr. Rasicot’s management of the talented CWMD workforce established an enduring vision, strategy, and focus nationwide on CBRN detection, training, and resources.  

Gary Rasicot will continue his service to the Department as the U.S. Coast Guard Deputy for Personnel Readiness to the Deputy Commandant for Mission Support.  In this role, Mr. Rasicot will oversee the Coast Guard’s human resources, force readiness, and Coast Guard Academy activities, and he will be instrumental in advancing the Commandant’s workforce transformation priorities.  

Please join me in congratulating Ms. Callahan on her new role, and thanking Mr. Rasicot for his service at CWMD and the USCG.