He's already declared Nat Emerg. in EO 12-21
"…..I therefore determine that serious human rights abuse and corruption around the world constitute an unusual and extraordinary threat to the national security, foreign policy, and economy of the United States, and I hereby declare a national emergency to deal with that threat…"
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I am pleased to inform you that I will Address the Nation on the Humanitarian and National Security crisis on our Southern Border. Tuesday night at 9:00 P.M. Eastern.