As U.S. envoys continue to negotiate with Iran, the United States is reportedly conducting the largest airpower buildup in the Middle East since the 2003 invasion of Iraq. The United States has deployed the USS Gerald Ford and USS Abraham Lincoln aircraft carrier strike groups to the region, along with fighter jets, refueling tankers, and air defense systems. Top U.S. officials have publicly demanded that Iran end uranium enrichment, curb its ballistic missile program, and sever support for its proxy network. Meanwhile, Tehran has sought to limit negotiations to its nuclear program in exchange for sanctions relief. On February 19, President Donald Trump stated that he will decide within ten days whether to take military action. It remains unclear whether potential strikes would target Iranian nuclear sites, missile stockpiles, or aim to topple the regime. In response to the heightened U.S. military presence, Iran has temporarily closed the Strait of Hormuz—one of the world’s most significant oil and natural gas chokepoints—to conduct live-fire drills.
Trump initially threatened military intervention in the wake of massive anti-government protests that began in late December 2025, which prompted a severe government crackdown estimated to have killed thousands of Iranians.
History of Iran’s Nuclear Program
Iran has pursued a nuclear program since at least 1957, with varying degrees of success. During a war with Iraq, Iran decided to develop nuclear weapons to ensure its security in the late 1980s. Consequently, Iran pursued agreements with China and Russia to support the program’s research throughout the 1990s. In the summer of 2002, the National Council of Resistance of Iran, an umbrella organization made up of Iranian dissident groups, exposed the existence of two Iranian nuclear sites that were hidden from the IAEA.
By 2003, diplomats launched an intensive effort to halt Iran’s nuclear program. Iran agreed, insisting only on keeping its centrifuges for nuclear energy. However, it did not follow through on its commitment to transparent reporting to the IAEA and continued covert activities, leading to a June 2004 rebuke and a September 2005 finding of non-compliance by the IAEA, paving the way for a future referral to the UN Security Council (UNSC). In 2006, the UNSC adopted Resolution 1696, the first legally binding call for Iran to suspend its uranium enrichment program. Over the next few years, the UNSC adopted a series of resolutions imposing crippling economic sanctions on Iran for its failure to suspend its enrichment-related activities.
Between 2011 and 2015, the compounding effects of international sanctions led Iran’s economy to contract by 20 percent and unemployment to rise to 20 percent. In 2013, Hassan Rouhani, a noted pragmatist, won Iran’s presidential election, campaigning on a promise to lift sanctions and restore the economy. Over the next two years, the United States convened several rounds of bilateral talks and led the other P5+1 coalition members—China, France, Germany, Russia, and the United Kingdom—in negotiations with Iran’s new leadership. These efforts culminated in the adoption of the Joint Comprehensive Plan of Action (JCPOA) in 2015. Once key parties signed the agreement, the UNSC approved UN Resolution 2231, paving the way for sanctions relief.
The JCPOA required Iran to reduce its stockpile of enriched uranium by 98 percent for fifteen years, cut the number of operating centrifuges by two-thirds for ten years, and provide inspectors access to enrichment facilities within twenty-four days if the IAEA suspects violations. Moreover, if the IAEA confirmed violations, the JCPOA allowed for the immediate reinstatement of sanctions. After the JCPOA entered into force on January 16, 2016, Iran received sanctions relief totaling nearly $100 billion. However, Iran continued to develop ballistic missiles, which, according to the United States, violated UN Resolution 2231.
Iran’s Regional Proxies
Though the JCPOA limited Iran’s nuclear ambitions, its regional ambitions continued to grow. Iran persisted in arming and training Shiite militants through its Quds Force—the international arm of the Islamic Revolutionary Guard Corps (IRGC)—which has exacerbated sectarian divisions in the Middle East. Iran has provided years of military aid and training to the Palestinian militant group Hamas, which enabled its October 7, 2023, attack on Israel. The Quds Force has also provided advanced armed drones to Hezbollah in Lebanon, trained and funded more than one hundred thousand Shiite fighters in Syria, supplied ballistic missiles and drones to Yemen’s Houthis, and helped Shiite militias in Iraq build missile capabilities.
The U.S. government considers Iran to be the foremost state sponsor of terrorism, spending more than one billion dollars on terrorist financing annually. There are between 140,000 and 185,000 IRGC-Quds Force partner forces across Afghanistan, Gaza, Lebanon, Pakistan, Syria, and Yemen.
Trump’s First-Term Clash With Iran
Because the JCPOA only addressed Iran’s nuclear program—and not its revisionism or ballistic missile programs—the first Trump administration withdrew the United States from the agreement, pledging to seek a more comprehensive deal. In 2018, the Trump administration began reimposing sanctions on Iran and demanded that European countries withdraw from the JCPOA as part of a new containment strategy. U.S. sanctions sparked the worst economic crisis Iran has faced in forty years, cutting Iranian oil exports by more than half and emboldening Iranian hardliners.
While the Trump administration pursued a strategy of maximum pressure to bring Iran to the negotiating table, Iran began to contravene the JCPOA’s restrictions on its nuclear program, raising tensions. In April 2019, the United States designated the IRGC a terrorist organization. When the Trump administration received intelligence of potential Iranian attacks on U.S. troops, it deployed bombers, carriers, and additional forces to the Middle East. Over the next month, six oil tankers in or near the Strait of Hormuz were attacked, which U.S. government officials blamed on Iran.
In late June 2019, Iran downed a U.S. Global Hawk drone in the Strait of Hormuz; President Trump ordered a cyberattack and the imposition of new sanctions in response. On December 31, Trump blamed Iran for backing protests that tried to seize the U.S. Embassy in Baghdad. Days later, tensions peaked when the United States killed Qasem Soleimani, the commander of Iran’s Quds Force, in a Baghdad air strike. In response, Iran said it would no longer adhere to restrictions under the nuclear deal, and it accidentally shot down a Ukrainian passenger plane while on high alert. In late 2020, Trump continued to ratchet up sanctions, and Iran boosted uranium enrichment to levels well beyond the limits of the nuclear deal after one of its top nuclear scientists was killed.
Conflict Between Israel and Iran
The outbreak of war between Israel, a close U.S. ally, and the Palestinian Iran-backed militant group Hamas in October 2023 escalated tensions between Iran and Israel. Iran-backed proxy forces ramped up strikes in protest of Israel’s military incursion into the Gaza Strip, including more than two hundred attacks on U.S. and Israeli targets in Iraq and Syria. In response, the United States ordered air strikes on two Iran-backed facilities on October 26, 2023, and eighty-five more Iran-affiliated targets in the two countries on February 2, 2024. The Houthis in Yemen and Hezbollah in Lebanon—both actors in Iran’s axis of resistance—also launched attacks from the Red Sea and Israel’s northern border with Lebanon, spurring fears of regional spillover.
In 2024, Israel and Iran’s confrontation shifted from indirect, proxy-based hostilities to direct exchanges of strikes. On April 1, a suspected Israeli air strike against an Iranian consular building in Damascus, Syria, killed two of its generals and five military advisors. Iran retaliated by launching over three hundred drone and missile attacks, the first time Iran had directly targeted Israel.
Following Israel’s killing of the leaders of Hamas and Hezbollah, Iran launched 180 ballistic missiles against Israel in October 2024. Israel then launched its largest direct attack on Iran, targeting its air defenses and missile production facilities. Israel’s decimation of Hamas and Hezbollah leadership, coupled with the downfall of the Bashar al-Assad regime in Syria, considerably weakened Iran’s axis of resistance in 2024.
Upon returning to office in 2025, U.S. President Donald Trump restored his maximum pressure campaign against Tehran while also initiating negotiations on its nuclear program—the first direct U.S.-Iran talks since he withdrew the United States from the JCPOA nuclear deal in 2018. Israel was wholly opposed to the negotiations and has maintained an unwavering commitment to dismantling Iran’s nuclear program. Israeli officials argue that Iran’s clandestine efforts to develop nuclear weapons would fundamentally alter the regional balance of power, posing a direct danger to Israel’s survival.
On June 12, the International Atomic Energy Agency (IAEA) declared Iran was violating its non-proliferation obligations for the first time in twenty years, prompting Iran to announce it would open a secret uranium enrichment site. The next day, Israel launched a unilateral military strike against Iran, targeting nuclear facilities, missile factories, senior military officials, and nuclear scientists. Iran’s Foreign Minister Abbas Araghchi declared the attack “an act of war,” and Iran retaliated by launching waves of drones and dozens of ballistic missiles. Israeli Prime Minister Benjamin Netanyahu described the operation as a last-resort effort to prevent Iran from acquiring nuclear weapons. Although the Trump administration had recently resumed nuclear negotiations, President Trump increasingly voiced support for Israel’s objectives and signaled his openness to regime change in Tehran.
Following a week of air strikes between Israel and Iran, the United States directly intervened in the conflict, attacking three Iranian nuclear sites in Fordow, Isfahan, and Natanz on June 21. The Trump administration claimed the strikes significantly hindered Iran’s capacity to achieve weapons-grade uranium, but the head of the UN nuclear watchdog assessed the program was set back by a matter of months. Trump is the first U.S. president to attack another country’s nuclear program and the first to explicitly join Israel in an attack on an adversary. Iran retaliated on June 23, launching a missile attack on U.S. forces stationed at the Al Udeid Air Base in Qatar; no casualties were reported. Trump announced a ceasefire later that day. Although both sides accused the other of continuing strikes, the truce has largely held.
