The conflict with Iran has come at a high political cost for U.S. President Donald Trump. With the Iranian regime not overthrown, Trump faces significant pressure both domestically and internationally. As debates continue within American politics over whether the war has been adequately justified to the public, the support of Republican lawmakers who have stood behind him so far is also eroding.

On June 3, the U.S. House of Representatives passed a war powers resolution aimed at halting Trump's further military action in Iran. The largely symbolic measure passed by a 215-208 vote, with four Republicans joining Democrats in a rare public rebuke of the administration's handling of the conflict that began in February.

This is another indication that Trump is facing pressure from within his own party. While a memorandum of understanding between the U.S. and Iran was announced and is set to be signed on June 19, it is just the beginning of complete peace negotiations, and the negotiation process will likely remain fragile. With the upcoming midterm elections and no final peace deal yet reached, Trump appears to be under pressure at home.

Considering intra-party politics, Trump is under double-edged pressure coming from two sides. On one hand, there is the Make America Great Again (MAGA) faction, which has criticized the Iran war from the beginning, and on the other hand, there is a faction that views efforts toward a deal with suspicion. This skeptical faction, often described as Iran hawks, could make it difficult for Trump to secure congressional support for any final nuclear agreement, particularly if it involves sanctions relief requiring congressional review.

In addition to the Republican Party's internal power struggles, Democrats are also applying pressure from the outside, albeit to a more limited extent. If no agreement is reached and the war does not at least come to an end, the Democrats could turn the midterm elections into an "Iran war election." This could affect election outcomes in some states, if not all. Under this scenario, going in with Israel could prove costly for Trump, further fueling the emerging debate surrounding support for Israel.

Split among Republicans

The party's MAGA wing has always been skeptical of U.S. foreign aid, not only to Israel but also to European allies and Ukraine. In recent years, they have also raised their voices when it comes to unconditional support for Israel. On the other hand, the Republican establishment is known for its strong commitment to Israel's security. They have rarely questioned U.S. support for Israel.

This divided approach toward Israel does not seem to be just a policy issue among party elites. A younger and more populist conservative demographic is also beginning to question the traditional Republican consensus on Israel and the extent of U.S. support for it.

While such concerns are not as openly voiced as they are among some Democratic voters, given the influence of pro-Israel figures within the Republican Party, this could signal a new era for the party and push party elites to pay more attention to their constituents.

Looming midterms

The 2026 midterm elections will be a crucial test for Trump and both his Republican allies and opponents. Facing the upcoming midterm elections under the shadow of the war is not something Trump wants. Therefore, he has a strong incentive to bring the conflict to an end sooner rather than later while preserving unity and cohesion within his party and maintaining the support of his base.

Trump came to power promising to end the never-ending wars in American foreign policy. He has always claimed to be a fierce critic of the Iraq War. In the first few months of his second term, he also presented himself as a president of peace, claiming to have ended many wars. Then came the 12-day Iran War, in which the U.S. role was limited to a surgical strike on Iranian nuclear facilities. However, the 2026 Iran War and the military operation in Venezuela marked a significant departure from that approach, involving direct and extensive U.S. military engagement.

By seeking a deal, Trump appears to be heading into the campaign season without a war in Iran. While costly, the war has not yet had catastrophic consequences for the American people. However, given his anti-war rhetoric during his campaign, starting a war is a major contradiction for Trump. Even before the war began, some MAGA figures, particularly over the Epstein files, had openly criticized him. And Trump, as always, did not shy away from publicly debating them.

Trump will need the support of the MAGA base for the midterm elections. Rising gas prices and inflation could become key factors driving a voter backlash. Many lawmakers, on the other hand, are concerned about the party's midterm strategy. Distracting voters from the negative consequences of the war will prove to be a significant challenge.

Polls show that a majority of those identifying as independents have a negative attitude toward the war and Trump's handling of it. While this is not yet the majority view among Republicans, it has the potential to influence the election. Lower Republican voter turnout and independent voters shifting their support to the Democrats could have serious political consequences in many constituencies.

At the end of the day, Trump, perhaps driven by a belief in a quick and decisive victory, has incurred considerable domestic political costs in the Iran war. As the conflict has dragged on, critical voices within the Republican Party have grown more vocal. Divisions had already emerged within the party, particularly regarding Israel’s role in U.S. foreign policy. On top of this, the war’s negative consequences may carry significant political repercussions for Trump in the upcoming midterm elections.