Kevin Lamarque / Reuters

Donald Trump’s closing message ahead of the midterm elections was that voters faced a choice between imminent national catastrophe and salvation—with the United States besieged by unauthorized immigrants, shadowy terrorists, and predatory trade practices that he alone could repel.

And the president, who enjoys wide latitude in foreign affairs and a Republican-controlled Senate, may largely be able to press ahead with his fiercely nationalist agenda even though voters responded by granting Democrats control of the House of Representatives.

Some of Trump’s top foreign-policy initiatives—new trade deals, a potential peace treaty with North Korea, his proposed border wall,  Space Force, and a nuclear-weapons buildup—require congressional consent and are all thus affected by the election results. But many are not.

The consequence is that the newly constituted House of Representatives will probably act more as an investigative body than a legislative one, with Democratic committee chairs presiding over a flurry of probes and hearings involving Trump and his administration.

And whether the subject is the president’s personal finances, harsh immigration policies, or obscure military engagements in Africa, these examinations will shine a bright light on the Trump administration’s activities, influence public opinion, and—to an as-yet-unknowable extent—restrict the president’s room for maneuvering on the world stage, as Rick Dearborn, Trump’s former White House deputy chief of staff, observed at the American Enterprise Institute ahead of the election.

“The more time [Democrats] spend bringing up administration officials to have to testify in front of Congress, the less time the administration officials have to execute what they’ve been asked to do by the president,” he said.

Here’s a rundown of the policies that could be most affected by the midterm results.

Trade

Trump has expansive authorities on trade, which may well be the animating theme of his next two years in office as he aims to transform the U.S. economy and pressure China and other economic rivals into making major concessions before the 2020 U.S. presidential election.

Hence why, despite the misgivings of Republican lawmakers, he has managed to withdraw the United States from a major multinational trade agreement, launch a trade war with the Chinese, and impose steel and aluminum tariffs on U.S. allies on national-security grounds.

But while the president generally doesn’t need Congress’s approval to scuttle trade pacts or relationships, he does need its help to establish new ones. It will likely fall to the next Congress to approve Trump’s renegotiated trade agreement with Canada and Mexico (and any future trade pacts with Japan, the European Union, and post-Brexit Britain).

That’s where things could get interesting. Congressional Democrats are divided on the value of free trade. Many support Trump’s efforts to get tough on what they perceive as other countries’ unfair trade practices, and the kinds of improved labor and environmental standards called for in the Trump administration’s proposed successor to NAFTA. There is, just maybe, a bipartisan deal to be cut.

At AEI, Dearborn said he expected the United States–Mexico–Canada Agreement to pass both houses of Congress (all that’s required is a simple majority in each). “If it’s going to be held up, it will be [so that the Democrats] can make a point on labor and environmental issues to try to … fire up their base as they head into the presidential election,” he predicted.

Immigration

Adam Smith, a Democrat from Washington State who’s in line to chair the House Armed Services Committee, told me one of his priorities in the next Congress will be to hold hearings on the “politicization of the military,” citing as one example the president’s deployment of thousands of U.S. troops to the border to deter incoming Central American migrants, just ahead of the midterm elections.

“I hate the way the Republican majority handled it when Obama was president, when Clinton was president—how they investigated everything,” Smith said. “I’m not talking about that. I’m talking about the House of Representatives doing its job, which is to ask questions and exercise oversight of the executive branch.”

The military shouldn’t be used for Trump’s “immigration war,” Smith added. (There will probably be no corresponding scrutiny in the upper chamber, where the Oklahoma Republican Jim Inhofe, who is slated to be the next chairman of the Senate Armed Services Committee, succeeding the late John McCain, has praised Trump’s troop deployment and has been a stalwart supporter of the president and his defense secretary, Jim Mattis.)

The big question here will be whether Trump can persuade Congress to fully appropriate funds for his wall along the U.S.-Mexico border. Congressional Republicans, who are split on the wisdom of Trump’s pet project, may attempt to provide the president with the $25 billion he needs before the Democrats take control of the House next year—risking a partial government shutdown in the process.

But if they fail to do so, Trump will have a couple of other options. He could try to secure funding from the Defense Department, something Smith has vowed to resist. “Mexico was going to pay for [the wall], right?” he asked sarcastically. “So why does the president keep asking for money?”

Or Trump could pursue some grand bargain with Democrats; say, bankrolling the wall in exchange for protecting young immigrants who arrived in the country as children from deportation. The agreement would then have to make it through the Republican-controlled Senate, and it’s far from clear that Democratic leaders—including the likely next House speaker, Nancy Pelosi—would cut any deal involving the wall in the first place.

Congress, which controls the budget, has the most leverage with the president when the White House needs money to do what it wants. The looming fight over the border wall could be a prime example of that reality.

As a result, Trump may end up with a mere chunk of wall and a new 2020 campaign talking point: Make the Democrats pay for not paying for the wall.

Russia

The 116th Congress will concentrate on two distinct but linked lines of inquiry: possible ties between Russia and the Trump campaign during the 2016 U.S. presidential election, and relations between Russia and the Trump administration during a period of heightened tension between Moscow and Washington.

On the latter front, the New York Democrat Eliot Engel, who is expected to soon head the House Foreign Affairs Committee, has indicated that he will investigate what Trump and Vladimir Putin discussed during their private one-on-one meeting in Helsinki in July of 2018. Engel may also pressure the administration to develop a broader campaign, including additional sanctions, to counter Russian aggression, something Republicans might support as well.

If installed at the helm of the House Armed Services Committee, which, along with its Senate counterpart, helps set annual U.S. defense spending, Smith could block two core components of Trump’s escalating arms race with Russia and China: a $1.2 trillion plan to upgrade the U.S. nuclear-weapons arsenal and a $13 billion proposal for a new military branch called the Space Force. Smith opposes both as unnecessary and unaffordable.

The California Democrat Adam Schiff, the likely next chairman of the House Intelligence Committee, told me he plans to investigate potentially explosive matters such as “credible allegations that the Russians may have laundered money through the Trump Organization” in order to determine whether U.S. policy is being shaped “by leverage that the Russians have over the president.” (Possible conflicts between national interests and the president’s personal and financial interests, from Panama to Saudi Arabia, are likely to be a common point of inquiry across House committees.)

On Wednesday, the president declared that he would adopt a “warlike posture” and refuse to work with the Democrats on issues such as trade if faced with such investigations in the House, portending further dysfunction for the U.S. government and its relations with Russia.

North Korea

The Democratic takeover of the House will spark hearings on the extent of Trump’s progress in denuclearizing North Korea. It could leave North and South Korea seriously concerned about the political standing—even the potential impeachment—of the president with whom they are currently negotiating nothing less than the future of the Korean peninsula.

Where the election results could matter most is if the parties defy the very long odds and reach a final accord before the end of Trump’s first term. Such a deal could involve North Korea giving up nuclear weapons in exchange for a peace treaty that would need to be ratified by the still-GOP-held Senate. And Trump would likely receive help in steering the agreement through the upper house from close, well-positioned Republican allies such as Inhofe, Jim Risch of Idaho, and Lindsey Graham of South Carolina, arguably the body’s leading voice on foreign policy.

Granted, the disarmament provisions would have to be pretty rigorous to satisfy a North Korea hawk like Graham. But the new Senate will nevertheless feature Republican leaders who will likely be far less critical of the president than McCain and the retiring Bob Corker were—particularly if they are moved to rally around their party leader while he’s in the crosshairs of empowered Democrats in the lower house.

Risch, who is in line to succeed Corker as head of the Senate Foreign Relations Committee, has a markedly different view of Trump’s North Korea policies than the current chairman. Whereas Corker once warned that Trump was leading the country to “World War III,” Risch has defended both the president’s aggressive approach early on in the administration and his more conciliatory tack in recent months.

“I know for a fact that the man sitting there representing me, us, America, has nothing but the highest ambitions for the security and safety of the United States,” Risch told me and other reporters when we met with him just before Trump’s summit with North Korean leader Kim Jong Un last summer.

Risch said that with respect to nuclear talks with North Korea and any ultimate agreement, he wished to exercise the Senate’s “advice and consent” power. “We don’t want to do anything that’s going to get in the way of what [the administration is] doing,” he noted. Criticizing the Obama administration for bypassing the Senate in reaching its nuclear deal with Iran, he suggested that the Trump administration wouldn’t make the same mistake. “The Constitution is very specific on how you get an agreement with the United States” rather than with an individual president, he told me.

The War in Yemen

The relationship between the United States and Saudi Arabia is under all sorts of pressure from Congress at the moment. Lawmakers from both parties have called for sanctions on top Saudi officials and the termination of arms sales to the kingdom over the murder of the journalist Jamal Khashoggi by agents of the Saudi state. It’s unclear, though, how far the next Congress will go in pressuring a reluctant president to adopt such measures against a critical U.S. ally.

Where the pressure is most acute, and where the probability of real change is highest, is with regard to the Saudi-led, U.S.-backed military intervention in Yemen’s civil war against Houthi rebels allied with Iran. The Trump administration recently called for a cease-fire and peace talks, and congressional Democrats and Republicans have proposed a variety of measures to redress the deepening humanitarian disaster in the country.

Smith, for example, along with the California Democrat Ro Khanna, has introduced a bill that invokes congressional war powers to end U.S. support for the Saudi air campaign. Even if the legislation doesn’t get through the House and the Senate, the goal is to “raise awareness,” Smith told me.

“I do not think Saudi Arabia has been honest about what they’ve been doing in Yemen,” he said. “They keep acting like they are minimizing civilian casualties, they’re not doing blockades, but the reports on the ground are different. I just don’t want the U.S. involved in that.”

The U.S. Role in the World

Congressional Democrats and Republicans alike tend to subscribe to a much more traditional vision of U.S. grand strategy in the world than Trump does—one in which allies aren’t treated as adversaries, rival powers such as Russia aren’t cozied up to, and American leadership of the international system isn’t dismissed as a rotten deal. (The rare instance in which Trump and many lawmakers in both parties are in agreement is in the belief that China is a growing economic and security threat to the United States, which suggests that the power struggle between the two nations might only get nastier in the coming years.)

Nevertheless, one larger ambition for Democrats in the House will be to present an alternative to the president’s America First vision. Schiff, for example, pointed to the challenges that rising authoritarianism is posing to liberal democracy everywhere from Brazil to Hungary to Turkey and the Philippines.

“This rise of authoritarianism is one of the most serious national-security threats facing the country,” Schiff argued. “We have a president who makes common cause with autocrats and has made the United States unrecognizable to a lot of our allies. I think it’s going to be vitally important that Congress step into the void and become the champion of democracy and human rights, because that role’s been abdicated by the president.”

The Democrats will seek to emphasize diplomacy and foreign assistance and deemphasize military solutions to the world’s problems, Smith told me.

“I don’t think we’re going to be able to come up with a bumper sticker,” he acknowledged. “Peace and stability through strength, cooperation, and alliances is the way I would put it.”

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