House Minority Leader Nancy Pelosi (D-Calif.) reacts with other House Democrats to returns from the 2018 midterm elections. (Erik S. Lesser/EPA-EFE) (Erik S Lesser/EPA-EFE/REX/Shutterstock)

Tuesday night, Democrats won control of the House of Representatives.

Already they’ve promised a raft of ambitious domestic shifts. Those will be hard enough without control of the Senate or the presidency. But look beyond the country’s borders, and things get tougher.

The Democrats cannot do much to change the president’s foreign policy course. “It’s not at all obvious that the midterms will have much effect on foreign policy,” said Richard Haass, president of the Council on Foreign Relations. “Under our system, almost all of the initiative resides with the executive branch. That’s not going to change."

But what the Democrats can do is turn up the heat with hearings and investigations. And that is exactly what they’re planning, leaders say. House leaders have promised greater scrutiny of Pentagon and State Department operations. They also are hoping to kick-start U.S. investment to combat climate change and global poverty.

They have also promised to use their perch to better understand Trump’s relationship with foreign powers and the influence his business dealings might have.

Rep. Adam Smith (D-Wash.), likely chairman of the House Armed Services Committee, told Vox he would use his new position to investigate the military’s disaster response and “lack of a consistent policy concerning civilian casualties.” He said he also would audit the Pentagon “to ensure that we are getting the best value for the taxpayer dollars we are spending.”

Smith also hopes to push back against Trump’s efforts to increase and modernize the U.S. nuclear arsenal.

Some on Smith’s committee want to go even further. Rep. Ro Khanna, who describes himself as a “foreign policy populist,” wants to invite the chairman of the Joint Chiefs of Staff, Marine Gen. Joseph F. Dunford Jr., to a three-day hearing to “justify every military deployment,” according to Vox.

Rep. Eliot L. Engel (D-N.Y.), who will likely lead the House Foreign Affairs Committee, told Vox he plans to prioritize oversight of the State Department and the U.S. Agency for International Development, which have been gutted by the administration. He is also keen to investigate the Trump administration’s potential conflicts of interest abroad.

Eliot said he is interested in strengthening the U.S. response to Russia’s election interference. And he intends to push to end America’s support for a Saudi-led coalition waging war in Yemen.

Democrats may restart Congress’s Russia probe into interference in the 2016 election. They could also push for investigations into Trump’s trade war with China and ties to Saudi Arabia.

But they may well find themselves pushing back against a president who becomes even more aggressive in his foreign policy approach, since he will have trouble moving domestic legislation through Congress.

“He wouldn’t be the first [president] to turn to foreign policy” after a midterm loss, Haass said. But since Trump has already charted a very independent foreign policy, Haass is not sure how different that would look.

“If he’s stymied domestically, it would possibly increase his view that foreign policy is a domain where he can ‘get things done.'” Haass said. But it “wouldn’t be a fundamental change, since he’s already acting relatively unconstrained.”

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