EXPLAINER - What to watch as Hegseth and Caine face Senate questions on Iran war funding

US Defense Secretary Pete Hegseth and Chairman of the Joint Chiefs of Staff Gen. Dan Caine are set to appear before the Senate on Tuesday as lawmakers weigh an $87 billion emergency spending package and seek answers about the Trump administration’s military strategy toward Iran. The hearing before the Senate Appropriations Committee comes at a critical moment for the administration following a sharp escalation in the US-Iran conflict that has left three American service members dead and raised questions about the duration, cost and objectives of the campaign. Hegseth and Caine, along with Agriculture Secretary Brooke Rollins, will testify in support of the White House’s supplemental funding request, which includes $67 billion for defense-related needs. The remaining funds are aimed at addressing other priorities, including efforts to contain an Ebola outbreak and provide assistance to US farmers. Why is Congress holding this hearing? The White House formally submitted the supplemental request to Congress on June 24, seeking additional resources to support ongoing military operations and other emergency programs. For the Pentagon, the funding would help cover the costs of the Iran conflict, including military operations, equipment and support for deployed forces. Lawmakers from both parties are expected to question Hegseth and Caine about how the Pentagon plans to use the money and whether the administration has a clear long-term strategy for dealing with Iran. The hearing will also serve as a major oversight opportunity, as Congress has received limited public briefings on the scope and objectives of US military operations since the conflict intensified. What questions will Hegseth and Caine face on Iran? The testimony will mark the first extensive public remarks by Hegseth and Caine since US military operations against Iran expanded in July. US forces have conducted strikes against Iran for 10 consecutive days as President Donald Trump seeks to pressure Tehran’s leadership and respond to Iranian attacks targeting commercial vessels attempting to navigate the Strait of Hormuz. Iran has retaliated by striking US military positions and allied facilities across the Gulf region, including locations in Kuwait, Jordan, Bahrain and Qatar. Democratic lawmakers on the committee are expected to press Hegseth and Caine over the deaths of three US service members — two in Jordan and one in Iraq — as well as the broader risks of continued military escalation. The Pentagon said Monday that nearly 100 US service members have been injured since July 7, though about 96% have returned to duty. How much is the war costing? The financial impact of the conflict is expected to be a major focus of the hearing. The administration has not publicly provided a detailed estimate of the total cost of the Iran campaign, and lawmakers are likely to ask the Pentagon for greater transparency on spending. Last week, Senate Democrats questioned Pentagon comptroller nominee Jules "Jay" Hurst about the cost of the conflict. Hurst, who had served as the Pentagon's acting comptroller and chief financial officer until May 20, when President Trump officially nominated him to assume the role on a permanent basis, told lawmakers that the US war with Iran cost an estimated $29 billion as of late May but acknowledged that the figure excludes damage to military facilities and other infrastructure. "I will give you the same answer I gave you during the posture hearing, that it was $29 billion at the time I left the position. If confirmed, I'm going to work," he said. The funding debate comes as Congress considers whether to approve billions of dollars in additional military spending while the conflict remains active and its timeline is uncertain. Will Congress approve the request? The supplemental funding package faces political challenges, particularly among Democrats whose votes may be needed for passage. When the White House submitted the request in June, many Democrats responded cautiously, criticizing the administration’s approach to Iran and seeking more details about the purpose and limits of the funding. Their concerns have largely remained unchanged, raising questions about whether the administration can secure enough bipartisan support. Hegseth and Caine last testified before Congress in early May during discussions of the Pentagon’s proposed $1.5 trillion budget request. The Pentagon’s last major media briefing on combat operations against Iran was held on May 5, leaving lawmakers and the public with limited information as the conflict has escalated.