Gonna put this here, although it could go a number of places. A look at the "National Security Strategy."
https://www.lawfaremedia.org/article/the-situation--why-did-the-white-house-write-this-national-security-strategy
Note here that the document is not defining “border security” as an important element of U.S. security or as one of the most significant elements of it. It is defining it as the single primary element of American security.
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I am willing to entertain the notion that the last several administrations may have underestimated the American people’s desire for a secure border. But to put the issue of border security as the top objective in one’s national security strategy is a kind of a nativist madness that is more about cultural—and let’s be honest, racial—anxiety about immigration than it is about any tangible security threat.
To call border security the primary element of national security, after all, you have to believe that controlling and limiting migration is more important to American security than, say, maintaining a functional and effective nuclear deterrence; having a military capable of protecting American interests at home and abroad, and stopping or deterring Russian and Chinese predations on allies. You have to believe it’s more important than having a coherent approach to protecting American critical infrastructure and cybersecurity and more important than stopping major terrorist operations.
Note that in this paragraph, the security concern is not any worry about activity that might attend uncontrolled migration—the terrorism, drugs, espionage, and human trafficking are almost after-thoughts in the paragraph. The threat is the migration itself. And the stakes? They are total. “A border controlled by the will of the American people as implemented by their government is fundamental to the survival of the United States as a sovereign republic,” the document warns darkly.