Fox News contributor Marc Thiessen said Monday that President Trump has made a series of mistakes in his attempt to secure funding for a border wall.

Trump declared a national emergency at the southern border last week, a decision that could divert billions of government dollars toward his long-promised wall. Trump also signed a bipartisan compromise that would provide nearly $1.4 billion for new border barriers.

Thiessen said on America's Newsroom that Trump "blew it" in 2018 when he passed on a deal of $25 billion in border security funding in exchange for a path to citizenship for DACA recipients. 

"He doesn't need to do a national emergency," he said of Trump. "Half of the money that he's gonna be using, he can get without a national emergency. It's just reprogramming authority that nobody contests."

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Thiessen said in actuality, Trump could have had $4.5 billion in federal funds for a wall without declaring an emergency.

"Half of the additional money is from reprogramming authority that the president has. So, he can take it from the Drug Enforcement Agency and from DOD drug enforcement money," he said.

He said conservatives should be worried about a national emergency, comparing it to a liberal president being able to declare a climate emergency and fund the Green New Deal.

"We don't want the President of the United States, as conservatives, to have unfettered power like this," he said.

Watch more above.

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