Answer:
The executive department organized in the 21st century was the Department of Homeland Security.
Explanation:
The United States Department of Homeland Security has the task of protecting the territory of the United States of America from terrorist attacks and to respond in the event of natural disasters.
In response to the September 11, 2001 attacks, President George W. Bush announced the formation of an internal security office to coordinate security efforts. The office was led by former Pennsylvania governor Tom Ridge, who also assumed the title of assistant to the president for internal security. Ridge began his work at the Domestic Security Bureau on 8 October 2001.
On November 25, 2002, the Department of Homeland Security was officially established following the promulgation of the Homeland Security Act in 2002. With its institution it was intended to merge all those governmental organizations and federal agencies which referred to internal security into a single department.
