Simplify the following text for a Grade 9 native English-speaking person.
Original: In January 2003 , the office was merged into the Department of Homeland Security and the White House Homeland Security Council , both of which were created by the Homeland Security Act of 2002 .
Simplified: In 2002 , because of the September 11 attacks in 2001 , Congress passed a bill called the Homeland Security Act , which created the Department of Homeland Security . Tom Ridge was the first leader of the Department of Homeland Security .