Editing Homeland defense (section)

==Full definition==
"Homeland defense (HD) is the protection of a [[sovereignty]], territory, domestic population, and critical defense [[infrastructure]] against external threats and [[aggression]], or other threats as directed
by the leader of that nation such as the [[president of the United States]]. The [[United States Department of Defense]] is partially responsible for the Homeland defense mission of the United States, and therefore leads the HD response, with other departments and agencies in support of DOD efforts."<ref name=defense>[https://fas.org/irp/doddir/dod/jp3_27.pdf FAS.ORG: '''''Homeland Defense, Joint Publication 3-27''''', 12 July 2007]<br>Definition p.6, Threat strategy p.20-21</ref>