What is the task of the united states department of homeland security?
to attack paramilitary terrorist groups
to aid in the prevention of terrorism abroad
to maintain the safety of all us citizens
to ensure the security of americans in other countries

To maintain the safety of all US citizens.

The Department of Homeland Security was created in order to protect the Americans from terrorists threat. The Department of Homeland Security works in order to prevent terrorists from using weapons of mass destruction such as nuclear, radiological,chemical,biological etc.

the world may never know