Homeland security has evolved since its inception over two decades ago, as has the mission, and to this week's point, the definition. From the Department of Homeland Security's Quadrenial Review, the focus has grown from its original protect the homeland to counter terrorism, secure our borders, manage the immigration system, secure cyberspace and critical infrastructure, respond to threats, and the latest addition of combating exploitation crimes (Department of Homeland Security, 2023). Under President Trumps first term, Joint Publication 3-27 described it as protection of US sovereignty, territory, domestic population, and critical infrastructure against external threats and aggression or other threats (Joint Chiefs of Staff, "Joint Publication 3-27, Homeland Defense," April 10, 2018. Unclassified. | National Security Archive, 2018). Looking further back still, President Obama defined it as identify and interdict threats; deny hostile actors the ability to operate within our borders; maintain effective control of our physical borders; safeguard lawful trade and travel into and out of the United States; disrupt and dismantle transnational terrorist, and criminal organizations; and ensure our national resilience in the face of the threat and hazards (National Security Strategy, 2011).

While these definitions may have varying scope and focus, they all have a central underlying theme that unites them. That theme is the protection of the homeland and her people. This theme has rung true from the Obama, Trump, and Biden administrations and will continue under President Trump's second term.

With respect to homeland security and homeland defense and their relationship with each other, it is symbiotic. By this, I mean that both exist to complement the other. Homeland security is focused on what it protects, the homeland, while homeland defense takes a global approach. This layered defense approach will increasingly be used over the coming years as nations seek to defeat the fortress Americana. SEND PEERS RESPONSE WITH CITATION