White House policy adviser Stephen Miller vigorously defended President Trump’s national emergency declaration, saying the commander-in-chief is on solid constitutional ground because Congress gave presidents the authority to use executive power decades ago.

“They passed a law specifically saying the president could have this authority. It’s in the plain statute,” Miller told host Chris Wallace on “Fox News Sunday.” “That’s the decision that Congress made and if people don’t like that they can address it.”

Miller said Trump is invoking the 1976 National Emergencies Act so he can reallocate funds from other sources – including from the Pentagon’s construction budget – to get $8 billion for a wall on the southern border.

Trump acted after Congress passed a spending bill last week that provided $1.3 billion for the barrier, far short of the $5 billion Trump had demanded.

But Wallace suggested Trump was overreaching and violating Article 1 of the Constitution that gives Congress the “power of the purse” to appropriate funds for projects.

Miller said the law gave Trump and past presidents the ability to access military construction funds.

“If the president were to say we’re going to use military construction funds to, say, increase a perimeter around a base in Bahrain, around a base in Syria, nobody would even say anything about it,” Miller explained. “And we have 4,000 troops on the border right now and as a result of that mission they need to secure those areas where they’re patrolling.”

Wallace said national emergencies have been declared 59 times since the law was passed and asked Miller to name one time when the president used the emergency powers to get funds after Congress turned him down.

“What you’re missing, Chris, is that national emergencies don’t have all the same authorities and the same justification,” Miller responded.

“I assume that, but there have been 59. Can you find one case like that?,” Wallace pressed.

“This authority specifically refers to using military construction funds,” Miller said.

Wallace pointed out that it happened twice – once by President George H.W. Bush during the Gulf War and once by President George W. Bush after Sept. 11.

“Can you name one foreign threat in the world today, outside the country’s borders that currently kills more Americans than the threats crossing our southern border?” Miller tried to deflect.

“You know the joy of this is I get to ask you questions,” Wallace said and then continued to urge Miller to name one case.

“The current situation pertains specifically to the military construction authority,” Miller said.

“But it didn’t involve taking money that Congress refused to appropriate,” Wallace said.

“They didn’t refuse to appropriate it. They passed a law specifically saying the president could have this authority,” the White House adviser said.