Democrats Take Congress and Challenge Trump's Foreign Policy

Democrats have won control of both chambers of the US Congress in a major midterm election victory, creating new obstacles for President Donald Trump's foreign policy agenda. The results, announced after Tuesday's elections, give Democrats greater authority over federal spending, congressional investigations, diplomatic appointments, and military funding, particularly concerning Iran, Ukraine, and Latin America.

According to analysis published by the Council on Foreign Relations (CFR), the Democratic majority will control the House and Senate, allowing the party to chair influential committees and oversee appropriations for defense, foreign assistance, and the State Department. However, Trump retains substantial executive authority and can veto legislation he opposes.

The election also strengthens Democratic influence over presidential nominations and congressional investigations. Senate committees can scrutinize diplomatic appointments, while lawmakers in both chambers can demand documents, summon officials, and issue subpoenas.

Democrats are expected to prioritize the economic consequences of Trump's policies, including the Iran war, international tariffs, housing costs, energy prices, and healthcare expenses. CFR senior fellow Rebecca Lissner said opposition to military intervention and tariffs had become significant political considerations among American voters.

Foreign Policy reported that Democratic lawmakers could use federal spending legislation to pressure the administration over military operations. Before the election, senior Democrats had indicated they would seek to restrict funding for the Iran war and military strikes against alleged drug-trafficking vessels near Latin America.

Brian Finucane, a senior adviser at the International Crisis Group and former State Department attorney adviser, identified congressional appropriations as a particularly powerful mechanism.

"Attaching a funding prohibition to a must-pass piece of funding legislation" would be the most effective "mechanism for forcing an end" to either the Iran war or boat strikes, Brian Finucane said.

He pointed to Congress's confrontation with President Richard Nixon in 1973 over the bombing of Cambodia as an example of how spending restrictions could influence presidential military decisions.

Finucane said Democrats would need to be prepared to "play hardball" and demonstrate the "political will" to use their majority. Such action could potentially "shut down" both the Iran war and what he described as "lawless boat strikes."

Joshua Shifrinson, a professor at the University of Maryland's School of Public Policy and an international security expert, highlighted another financial consequence of the conflict: the future of American military installations in the Middle East.

"Our bases there are going to need to be rebuilt or moved elsewhere. They've been heavily hit by Iran. That's an appropriations issue 101," Shifrinson said.

He added that lawmakers could "move the needle" on decisions involving American military facilities in the Middle East and Europe, as well as continued support for Ukraine.

Shifrinson also argued that Democratic lawmakers "can and should" use their investigative authority to examine foreign policy decisions and potential conflicts of interest.

"Investigative powers of controlling committees to call hearings on any number of issues, ranging from Iran war oversight to foreign influence over U.S. policy, which would include corruption by the Trump family or potentially illicit foreign dealings," Shifrinson said.

He predicted that "High-level investigations of all these facets of foreign policy … are very likely going forward."

Finucane separately identified potential investigations into the Trump family's international business interests as a "substantial theme for oversight in the House and potentially in the Senate." He said Democratic lawmakers had already "not so subtly" indicated "that this is coming down the road" through correspondence with the administration.

Venezuela is expected to receive particular attention. According to Americas Quarterly, Representative Joaquin Castro could use his anticipated leadership of the House Western Hemisphere Subcommittee to investigate the administration's oil arrangements involving Venezuela.

Representative Gregory Meeks, expected to chair the House Foreign Affairs Committee, has also warned foreign political figures against intervening in American elections. Referring to Colombian political activity surrounding a US congressional race, Meeks said, "Congress will be watching."

Senator Chris Coons, expected to lead the Senate Foreign Relations Committee, has previously challenged the administration's Venezuela policy, including its failure to consult Congress before the removal of Nicolás Maduro and subsequent military decisions.

Caracas Chronicles reported that Democrats had secured at least 228 House seats and 54 Senate seats in the results available at publication. The party also won several governorships, strengthening its position beyond Washington.

The publication identified Robert Garcia's expected leadership of the House Oversight Committee as another significant development for Venezuela. Garcia has sought accountability concerning more than $13 billion in Venezuelan oil revenue and requested communications involving companies including Chevron, ExxonMobil, Vitol, and Trafigura.

The incoming majority could also investigate the administration's foreign assistance decisions. CFR fellow Sam Vigersky said Democrats would examine the dissolution of the United States Agency for International Development, the withholding of previously approved aid, and changes to the administration of humanitarian assistance.

Latin American immigration policy will also face scrutiny. Americas Quarterly identified Immigration and Customs Enforcement detention practices, spending, and the transfer of migrants to El Salvador's CECOT prison as potential subjects of congressional investigations.

Nevertheless, the Democratic majority faces constitutional and political limitations. Most legislation in the Senate requires 60 votes to advance, while overriding a presidential veto requires a two-thirds majority in both chambers. These restrictions could prevent Democrats from directly reversing several major Trump administration policies.

Democrats are scheduled to assume their congressional majority when the new Congress convenes in January 2027, placing control of congressional committees and federal spending negotiations at the center of the next phase of US foreign policy.