State Department Report 4: Iran's Threat to Maritime Security

State Department sealOn September 25, the State Department's Iran Action Group released a report detailing Iran’s support of terrorism, missile program, illicit financial activities, threat to maritime security, threat to cybersecurity, human rights abuses, and exploitation of the environment. “Today, the United States is publishing a full record of the Islamic Republic’s hostile behavior abroad and its repression at home beyond the continued threat of the nuclear program,” wrote Secretary of State Pompeo in the report’s introduction. “It is important for the world to understand the scope of the regime’s recklessness and malfeasance.” The following is the section on maritime security.


Chapter Four: Iran’s Threat to Maritime Security 


The Islamic Republic poses a major threat to freedom of navigation and maritime security from the Persian Gulf to the Red Sea. Iran’s Islamic Revolutionary Guards Corps Navy (IRGCN) directly challenges global economic stability and the broader regional security architecture. Islamic Republic officials, including high-level Islamic Revolutionary Guards Corps (IRGC) commanders, have threatened to close the Strait of Hormuz, the narrow waterway in the Persian Gulf through which 20 percent of global petroleum passes. Iran has also taken its proxy wars to the sea. The regime provides weapons and advisors to the Houthi militants in Yemen, who in turn have targeted warships and commercial shipping in the Red Sea. 


The Islamic Republic has used the sea to confront its Gulf neighbors as well as U.S. interests and has a clear objective of expanding its power in the Persian Gulf and beyond. The IRGCN’s fast-attack small crafts have engaged in “unsafe and unprofessional” harassment of U.S. naval vessels in international waters on numerous occasions, according to the commander of U.S. Central Command, General Joseph Votel. In 2017, the U.S. Navy recorded 14 such instances while in 2016 and 2015 it recorded 36 and 22, respectively. These incidents presented a high risk of collision between IRGCN and U.S. naval vessels. In July 2017, an IRGCN vessel came within 150 yards of the USS Thunderbolt in the Persian Gulf, forcing it to fire warning shots. In another incident in March 2017, USNS Invincible was forced to change course to avoid collision with multiple approaching IRGCN fast-attack small crafts. The IRGCN threat to the U.S. Navy extends beyond its fast-attack small boats. The IRGCN has utilized drones to approach U.S. naval assets. In August 2017, an unarmed Iranian drone flew close to the USS Nimitz as fighter jets landed at night, threatening the safety of the American pilots and crew. 

The regime’s malign maritime behavior extends beyond the Persian Gulf to the Red Sea. Its support of Houthi militants in Yemen, which presents an escalated threat to both military and commercial interests. In January 2017, a remotely detonated marine craft attacked the Saudi Royal Navy Frigate, Al Madinah. The U.S. Navy determined that the craft was likely provided by the IRGC. Since then, the Houthis have threatened and carried out attacks against Saudi commercial vessels, including a July 2018 attack on a Saudi tanker in the Red Sea. In October 2016, the Iranian-supported Houthi militants fired anti-ship cruise missiles at U.S. warships in international waters just north of the Bab-al-Mandeb. The attacks came just one week after militants struck the Emirati vessel Swift, disabling the transport ship. The Houthis have also placed crude naval mines near commercial shipping routes in the Red Sea, threatening freedom of navigation and the free flow of commerce in the region. 

The expansion in Houthi maritime offensive capabilities reflects the persistent malign and destabilizing influence of the IRGC in the region. In 2016, the UN Secretary General expressed concern over Iran’s illicit arms shipments following the seizure of an arms shipment by the U.S. Navy in the Gulf of Oman. The U.S. concluded that the shipment originated from Iran and was bound for Yemen, in clear violation of a UN Security Council arms embargo on Houthi militants. Iran has also engaged in the illicit shipping of arms in other regions. In 2010, Nigerian officials uncovered an arms cache on board a commercial vessel in Lagos, demonstrating the risks posed by the Islamic Republic exploiting commercial shipments for malicious activities beyond the Persian Gulf and Red Sea. 

The Islamic Republic has also engaged in politically motivated seizures of commercial vessels, intended to project influence at home and abroad. In April 2015, IRGCN vessels fired shots across the bow of the Marshall Islands-flagged cargo ship Maersk Tigris near the Strait of Hormuz. The IRGCN then forced the vessel to dock at the Iranian port of Bandar Abbas. Iranian officials held the vessel for a week on charges of outstanding debt. The incident demonstrated the regime’s lack of regard for international norms and laws. Iran’s Islamic Revolutionary Guards Corps Navy seized Maersk Tigris cargo ship and held the vessel for a week


Iran’s illegal detention of Western sailors stands as one of the Iranian regime’s most provocative acts. Most recently, on January 12, 2016, the IRGCN seized two U.S. Navy riverine boats. They claimed the vessels illegally strayed into Iranian waters following engine failure, and detained ten U.S. sailors for a period of 15 hours. A Department of Defense investigation into the incident concluded that Iran violated international law by impeding the boats’ exercise of the right of innocent passage. It also determined that Iran violated the sovereign immunity of a U.S. vessel by boarding, searching, and seizing the boats, and by taking photographs and video recordings of the crew. 

In another highly provocative incident, the IRGCN boarded and seized the Royal Navy’s HMS Cornwall near the mouth of the Shatt al-Arab waterway in March 2007. For 15 days, the Iranian government detained the British sailors patrolling the waterways. According to a report on the incident by the UK House of Commons Foreign Affairs Committee, the Iranian regime claimed that the sailors confessed to engaging in patrols of Iranian waters illegally. The UK government definitively refuted the claim, providing evidence that the British vessel was 1.7 nautical miles inside Iraqi territorial waters. The Iranian regime then changed the coordinates of where they claimed the vessel had been captured, and refused to release the sailors. The detained sailors later stated that they were blindfolded, held in isolation, and threatened with up to seven years in prison if they did not confess to straying into Iranian waters. 

During the course of the two week ordeal, the UK Foreign Office froze bilateral diplomatic ties with Iran, the United Nations Security Council issued a statement of “grave concern” over the sailors’ detention, and the European Union called for the immediate and unconditional release of the detainees. Then-President Mahmoud Ahmadinejad agreed to their release after two weeks of negotiations, although he continued to insist that the crew had “invaded” Iranian waters. In fact, Ahmadinejad presented medals of honor to the IRGC commanders responsible for illegally detaining the sailors and insisted Iran had every right to put the sailors on trial, calling their release a gift to the British people. Iran’s illegal detention of sailors at sea is consistent with the regime’s broader policy of illegally detaining foreign and dual nationals on spurious charges.

Click here for the full report.