Secretary of War Pete Hegseth warned that more casualties are expected in the ongoing Operation Epic Fury in Iran, with seven U.S. soldiers having been killed so far in the fighting.

Hegseth made the comment during an interview with CBS’ "60 Minutes" that aired on Sunday.

"The president's been right to say there will be casualties," Hegseth said. "Things like this don't happen without casualties."

"There will be more casualties," he continued. "And no one is — I mean, especially our generation knows what it's like to see Americans come home in caskets, it's — but that doesn't weaken us one bit. It stiffens our spine and our resolve to say this is a fight we will finish."

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Six U.S. service members were killed in a March 1 Iranian drone attack in Port Shuaiba, Kuwait, while supporting Operation Epic Fury. The U.S. military said a seventh service member died of injuries from an Iranian attack on troops in Saudi Arabia on March 1.

The U.S. and Israel last week launched joint strikes against Iran. Iran has retaliated, launching strikes against Israel and neighboring Gulf Arab states, including Qatar and Saudi Arabia.

Iranian Foreign Minister Abbas Aragchi on Sunday told NBC News’ "Meet the Press" that if the U.S. deploys ground troops in Iran, "we have very brave soldiers who are waiting for any enemy who enters into our soil, to fight with them and to kill them and destroy them."

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"We never give up, we never surrender, and we continue to resist as long as it takes," he said. "We continue to defend ourselves and we are defending our territory, our people and our dignity. And our dignity is not for sale."

When reporters asked President Donald Trump aboard Air Force One on Saturday about potential ground troops being used in the Iran operation, the president said there would "have to be a very good reason."

"And I would say if we ever did that, [Iran] would be so decimated they wouldn't be able to fight at the ground level," Trump told reporters.

The Associated Press contributed to this report.

Within hours of American munitions striking Iranian soil, Ukrainian President Volodymyr Zelenskyy posted a statement that the Western press largely treated as a diplomatic footnote, but it was a signal that what happens in the skies over Tehran has a direct impact on the ground in Ukraine.

President Zelenskyy explicitly endorsed the strikes, called Iran "Putin's accomplice," noted that his country has absorbed over 57,000 Iranian-supplied drone attacks, and took aim at Moscow: "Whenever there is American resolve, global criminals weaken. This understanding must also come to the Russians."

Zelenskyy’s framing of the war in Iran through the lens of Ukraine's war is not incidental. Whatever Washington's stated objectives, the president, who has lived through the Ukraine conflict since the 2022 invasion, understands that Iran has been an active accomplice in Russia's war against Ukraine, and the United States has now acted against that accomplice.

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By striking the Iranian regime that provided the Shahed drones to Russia (and the ability to manufacture them) that have terrorized the Ukrainian civilian population for over four years, Washington has taken out a key Russian ally, which will negatively impact Russia’s ability to wage war in Europe.

When Iranian-provided drones began falling on Kyiv in October 2022, reducing apartment blocks to rubble and plunging cities into darkness, the world quickly learned a new word: Shahed. The Shahed-136 is not a sophisticated weapon. It is not fast (though Russian improvements have increased its capabilities significantly). It is not quite as precise as a cruise missile. What it is, and what it was always designed to be in Russia's hands, is a weapon of civilian terror.

Russian Shahed’s targets power stations and apartment buildings. The destruction they reap contributes to the blackouts that leave families without light and heat in winter. It is the triangular silhouette Ukrainians have learned to dread in the night sky, the low distinctive buzz from its propeller that sends people running for shelters. I have watched Shaheds glide through Ukrainian airspace toward civilian targets. I have stood with interceptor teams in the darkness doing everything they could to bring Shaheds down before they found their targets. The images of these drones flying into buildings in Kyiv represent the human toll of Iran’s pernicious contribution to the war in Ukraine.

By early 2023, Iran signed a $1.75 billion contract for additional drones and complete manufacturing blueprints. Russia subsequently built its own production facility in Tatarstan. Ukrainian intelligence estimates Russia now produces up to 1,000 modified Geran drones per day using Iranian-derived technology. In essence, Tehran handed Moscow the blueprint for a terror campaign against civilians that Russia has since industrialized on its own soil.

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Beyond drones, Iran delivered nearly $3 billion in ballistic and surface-to-air missiles before and during the invasion, including hundreds of Fath-360 ballistic missiles, numerous anti-aircraft systems, and hundreds-of-thousands of artillery shells, with total weapons value exceeding $4 billion.

Iranian munitions replenished Russia’s stockpile, dashing Western hopes that Russia might quickly run out of shells, drones, and missiles. In return, Russia offered Iran S-400 air defense systems, Su-35 fighter jets, nuclear reactor construction and geopolitical cover at the UN Security Council. A 20-year strategic partnership was formalized in early 2024. This was an axis built across military, nuclear, financial, and diplomatic dimensions, and due to U.S. action in Iran, this axis has crumbled in spectacular fashion. In a recent statement, Russian Foreign Minister Dimitry Peskov stated that Russia would not honor its defense agreement with Iran because he signed the agreement with Ayatollah Khameini, and Khamenei has been killed.

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However, Russia's most important strategic partner, China, continues to supply vast quantities of microelectronics and components for Russia’s military-industrial complex at a scale Iran could not match. But Beijing has carefully avoided direct lethal hardware transfers to preserve a degree deniability. Iran, on the other hand, filled the gap China deliberately left open: front-line weapons and production blueprints, deployed without hesitation.

Russia has fully indigenized Shahed production, even improving on the original design with the more sophisticated and expensive Geran variants. The Iranian government’s 50-year legacy of terror will live on not only in Middle Eastern states, but in Europe for as long as the war in Ukraine continues.

With the U.S. campaign promising to last for at least several weeks, Iran's capacity to supply additional ballistic missiles is now compromised. Its ability to upgrade drone designs at home and deliver replacement components is degraded. Moreover, every Russian asset potentially diverted to shield a battered Iran, air defense systems, aircraft components, logistics, is an asset unavailable in Zaporizhzhia or Kherson. Moscow is now burdened by a weakened, desperate partner at precisely the moment it can least afford the distraction.

This represents a different kind of pressure on Russia than sanctions or battlefield aid — one that works through the partnership networks and supply chains that have sustained the Russian war effort. Zelenskyy's prescient statement that every act of aggression ultimately meets a just response was directed towards Moscow and Tehran. While Ukraine was not Washington's primary consideration when President Trump decided to strike Iran, the calculus of the war in Ukraine will become more complicated for Russia, and that’s a good thing for Ukrainians fighting for their very right to survive.