The White House on Sunday defended President Trump’s declaration of a national emergency at the southern border and sought to clarify his contradictory statements about its necessity, marking the start of what’s expected to be a drawn-out fight over funding the construction of a wall amid mounting legal challenges and objections from Congress.

Trump’s announcement last week — an attempt to circumvent Congress by redirecting taxpayer money to pay for 230 miles of barriers along the Mexican border — has led to lawsuits and protests. California’s attorney general said he estimated about a dozen states would join a lawsuit against the White House that his office would file Monday. Various groups have held demonstrations against the declaration across the country.

Critics of the administration’s move, which calls for diverting billions of dollars already appropriated to the Defense Department, have seized on some of Trump’s comments as proof he did not need to declare a national emergency. “I could do the wall over a longer period of time,” Trump said Friday during a Rose Garden speech. “I didn’t need to do this, but I’d rather do it much faster.”

In an interview on “Fox News Sunday,” White House senior policy adviser Stephen Miller insisted the emergency is real, saying there was an “increasing number of people crossing” and “a huge increase in drug deaths” since George W. Bush was president. When host Chris Wallace countered with government statistics that show attempted crossings are at their lowest levels in nearly four decades and that most drugs are intercepted at ports of entry, Miller demurred.

“You don’t know what you don’t know, and you don’t catch what you don’t catch,” Miller said. “But as a matter of national security, you cannot have uncontrolled, unsecured areas of the border where people can pour in undetected.”

When Wallace pressed him on why Trump had said he “didn’t need to do this,” Miller doubled down. “What the president was saying is that, like past presidents, he could choose to ignore this crisis, choose to ignore this emergency as others have,” he said. “That’s not what he’s going to do.”

Lawmakers, including some Republicans, are divided as to whether the emergency declaration is legitimate or a power grab that could set an undesired precedent. Democrats are preparing a joint resolution to repeal the national emergency in coming weeks, and they expect some Republicans will cross the aisle to pass it.

Even if Congress passes such a resolution, Trump would probably veto it, Miller suggested Sunday. “He’s going to protect his national emergency declaration, guaranteed,” he said, insisting that by late 2020, “hundreds of miles” of new barriers will have been built along the border. “If the president can’t defend this country, then he cannot fulfill his constitutional oath of office.”

Sen. Tammy Duckworth (D-Ill.) said it was unclear whether there would be enough members of Congress to override a presidential veto but that many senators were alarmed by the emergency declaration. She said that even if one agreed with Trump that there is an emergency at the border, a wall would not be the most effective way to address it.

“If he wants to appropriate more money to put folks — more agents at the border, to put more people at the ports of entry … we can have those conversations,” Duckworth told Martha Raddatz of ABC News’s “This Week.” “But to take money away from [the Department of Defense] in order to build this wall that is essentially a campaign promise, I think, is really wrong priorities. And I think it’s very harmful to the country.”

Duckworth listed several projects that could be jeopardized by the diversion of military funds, including the planned construction of training facilities and aircraft hangers.

Republicans have been split on the issue, with some fully backing Trump and others cautioning that allowing an emergency declaration now would set a precedent for future Democratic presidents to do the same.

“This is an emergency. I mean, what are we on now, the fifth caravan?” Rep. Jim Jordan (R-Ohio) said Sunday on “This Week,” referring to groups of migrants from Central America who have traveled to the U.S. border, mostly to seek asylum.

Sen. Lindsey O. Graham (R-S.C.) said Sunday on CBS News’s “Face the Nation” that he supported Trump’s decision, even if the diversion of military construction funds to build a border wall meant jeopardizing projects such as the construction of a middle school in Kentucky and housing for military families.

“I would say it’s better for the middle school kids in Kentucky to have a secure border,” Graham said. “We’ll get them the school they need. But right now, we’ve got a national emergency on our hands.”

Rep. Will Hurd (R-Tex.), however, whose district includes more than 800 miles of the U.S.-Mexico border, said on “Face the Nation” that he opposes Trump’s declaration of an emergency, warning that it “sets a dangerous precedent.”

“Our government wasn’t designed to operate by national emergency,” he said. “We’re almost in uncharted territory.”

The promise of legal challenges to Trump’s emergency declaration came almost immediately. California Attorney General Xavier Becerra (D) said the state would file the suit on Monday, noting the irony that it would arrive on Presidents’ Day.

“We’re going to try to halt the president from violating the Constitution, the separation of powers, from stealing money from Americans and states,” Becerra said in a CNN interview Monday. When asked whether California would have standing to challenge the declaration, because Trump appears to be focused on building a wall in Texas, Becerra said, “If dollars are taken from states that have a purpose for those uses, then we are harmed.”

Becerra said Trump was engaged in “theater” to circumvent Congress in appeals to his base. “The president admitted he didn’t need to do this because it’s not an emergency; he admitted he expects to lose in court; he admitted that there was no crisis on the border,” he told CNN.

Several groups have initiated legal action against the move. On Friday, the advocacy group Public Citizen filed a lawsuit in U.S. District Court in Washington seeking to block Trump’s declaration on behalf of three Texas landowners and an environmental group. Also on Friday, Citizens for Responsibility and Ethics in Washington sued the Justice Department, accusing it of failing to provide documents — including legal opinions and communications — related to the president’s decision to declare a national emergency.

The Center for Biological Diversity, an environmental group, filed suit saying the president has failed to identify a legal authority to take such an action. The group’s complaint also warned that a border barrier would prevent wildlife from being able to freely pass in their natural habitat “and could result in the extirpation of jaguars, ocelots, and other endangered species within the United States.”

The American Civil Liberties Union said it was preparing a lawsuit arguing that Trump cannot legally redirect taxpayer money during an “emergency” unless it’s for military construction projects that support the armed forces.

Over the weekend, Acting Defense Secretary Patrick Shanahan said he would begin to examine projects that could be delayed or canceled to free up funds. Speaking to reporters, Shanahan said the military’s Joint Staff had been conducting a “mission analysis” on ways to deal with drugs and migrants at the border. “Based on that, we can do an assessment of what would be appropriate,” he said.

Shanahan said he had leeway to determine a final figure from available funds that would be used for border-related activities — $3.6 billion from designated military construction funds. He said the military’s service secretaries would be involved in identifying affected projects.

“All of this money has been assigned for different purposes, so it comes down to: What are you going to trade off?” he said.

Felicia Sonmez, Tony Romm, Missy Ryan, Devlin Barrett and Alex Horton contributed to this report.

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