Rep. Adam Smith (D-Wash.) is poised to take over as chairman of the House Armed Services Committee, which oversees the U.S. military and its funding. (Chip Somodevilla/Getty Images)

The Democratic takeover of the House poses challenges to the Trump administration’s plans to create a Space Force, augment the American nuclear arsenal and draw on military funds to build parts of the border wall, as the Pentagon faces an era of greater scrutiny and tighter funding.

Leading the charge for the Democrats on military issues is likely to be longtime Seattle-area congressman Adam Smith, who is poised to take over as chairman of the powerful House committee that oversees the U.S. armed forces and their funding.

Smith has established a reputation as a defense budget hawk, regularly pressing Republicans on the committee on how the country can afford to reduce government tax revenue while increasing defense spending. The annual defense budget reached $716 billion this year and included the largest baseline budget excluding active overseas deployments since World War II.

Even before the Democrats won the House on Tuesday, the Trump administration was pursuing plans to spend by 4.5 percent less on the military than it had initially planned for next year. The move came in response to a 17 percent increase in the federal deficit in 2018, the largest jump in six years, which resulted in part from the confluence of factors Smith predicted.

How much is spent on defense will depend on what caps the Republican-controlled Senate and the Trump administration broker with House Democrats for next year. House Democrats are likely to push for a greater share of nondefense spending to fund domestic priorities.

The most high-profile military expenditure Smith has taken aim at in recent years is a vast overhaul of the nation’s nuclear forces, estimated to cost some $1.2 trillion over 30 years including sustainment.

President Barack Obama signed off on the modernization plans as part of a deal to secure the Republican-controlled Senate’s ratification of the New START Treaty in 2010. 

But Smith has described the overhaul — which includes introducing a new air-launched cruise missile in addition to new nuclear bombers, submarines and intercontinental ballistic missile systems — as too expensive and unnecessary. He also opposes the low-yield nuclear warheads and cruise missiles the Trump administration wants to put on submarines.

Smith is also against Trump’s proposal to create a Space Force. He agrees with prioritizing space as a military domain but says the Pentagon does not need an entirely new and costly bureaucracy that would come with creating a separate military branch.

“We must do a better job of dealing with space as a national security priority,” he said in a statement. “I will continue to work toward a smarter, more effective approach.”

Apart from trying to scale back what he sees as unnecessary spending, Smith is likely to focus on forcing the Pentagon to answer more questions in public about its military programs and deployments, including Trump’s recent order to send active-duty forces to the border with Mexico.

In an Oct. 28 op-ed in the online publication Defense One, Smith argued that the Trump administration had wrapped the Pentagon in “a blanket of unaccountability” by seeking to roll back “transparency norms that have been in effect and functioning well since the mid-twentieth century.”

He said the administration had curtailed the Pentagon’s interactions with the news media, prevented the public release of cost schedules and weapons system assessments and sought to prevent defense officials from testifying before Congress.

“The message from the top has been to withhold information from Congress, the public, and the press, even as President Trump has simultaneously taken inappropriate steps to politicize the military,” Smith wrote.

In particular, Smith recently promised to get answers from the Pentagon about the justification for Trump’s troop deployment to the southern border.

“We would ask the Pentagon to come in and explain to us in an open public hearing what they’re doing and why,” Smith told Washington Post opinion writer Greg Sargent. “I don’t think we should let the president get away with this type of policy with no justification and no explanation for it.”

Smith spearheaded a letter sent by 108 House Democrats questioning the border deployment and separately decrying the use of Pentagon funds to build a wall along a stretch of the border in Arizona where a military bombing range abuts Mexico.

The letter criticized the Pentagon for approving $7.5 million in advance-planning funds for a roughly 35-mile border barrier at the Barry M. Goldwater Range. House Democrats said the barrier could cost as much as $450 million. Defense Secretary Jim Mattis has defended the structure as a way to prevent migrants’ endangering themselves by entering the range.

Smith is also concerned about the money the Pentagon spends to maintain bases and other infrastructure that the military has formally said it does not need. He has been pushing for Congress to begin a Base Realignment and Closure exercise, better known as BRAC, to get rid of excess military infrastructure.

Mattis followed previous secretaries of defense in calling for a BRAC in 2017, but he didn’t do so amid the budget largesse of 2018. The issue is likely to resurface as the Pentagon looks to economize under increased budget pressure.

Congress has not permitted the Pentagon to undertake a BRAC since 2005, largely because lawmakers have not wanted to risk the unpopular closure of bases in their districts. In 2016, the Pentagon predicted that some 22 percent of its bases would qualify as excess capacity by 2019, what defense officials have described as billions of dollars of wasted money.

While the Democrats favor retaining the Obama administration’s policy of allowing transgender individuals to serve in the military, the matter remains tied up in the courts, and it is unclear whether its new leverage in the House will allow the party to press the matter.

Democrats have also been particularly vocal about the Pentagon’s failure to properly account for civilian casualties caused by U.S. military airstrikes. They are likely to press the Defense Department to implement measures in this year’s annual defense policy bill aimed at increasing accountability and oversight of the process for identifying whether the military caused such deaths.