Media Guide: Naval Incidents between the US and Iran

By Research Fellow Gabriela Billini

Naval incidents between American and Iranian ships in the Persian Gulf have recently received increased media attention. Although such incidents have been occurring for some time, the new US administration and changing political environment in Iran have heightened their significance. In keeping with the goal of our Media Guide series to clarify and explain topics in US-Iran relations, we hope this guide will promote increased understanding of the issues at hand.


Where do most incidents at sea between the US and Iran occur? 

Most naval incidents between the U.S. and Iran occur in the Persian Gulf, and specifically in the Strait of Hormuz.

The Strait of Hormuz is a critical strategic maritime area that is 35 to 60 miles wide, located between Iran and the Arabian Peninsula, at the eastern end of the Persian Gulf. The Strait is under Iranian and Omani control and 17 million barrels of oil – about 30% of the world's maritime-traded oil (including Iranian, UAE, Qatari, Iraqi and Saudi oil) – passes through the Strait daily.

The Persian Gulf is part of the Indian Ocean and stretches between the Iranian Plateau and the Arabian Peninsula. With an area of 93,000 square miles and a length of 615 miles, the Persian Gulf is bordered by countries containing the largest oil reserves in the world. There are eight states that border the Persian Gulf: Iran, Iraq, Saudi Arabia, Kuwait, Oman, Bahrain, Qatar and the United Arab Emirates. Saudi Arabia, Iran and Iraq are the largest oil-producing nations of the group. In contemporary history, the Persian Gulf is remembered as a battleground for the 1980-1989 Iran-Iraq War, and the 1990 Iraqi invasion of Kuwait, which resulted in the first Gulf War.


What are the incidents between US and Iranian ships that I hear about in the news?  

Incidents between US and Iranian ships typically occur when Iranian ships “rush” towards American ships, requiring American ships to change course to avoid collision. The US government views Iranian ships in this situation as hostile, particularly due to the lack of radio communication. Since naval warfare often advantages the first party to attack, communication at sea is critical. Some examples of these incidents are described below:

On January 12, 2016, just four days before Implementation Day of the Joint Comprehensive Plan of Action (JCPOA), the Islamic Revolutionary Guard Corps detained two American Navy ships carrying ten officers in the Strait of Hormuz.  The US claimed that the ships were on a routine mission to Bahrain and accidentally strayed into Iran’s territorial waters due to mechanical failures. Iran held the soldiers to investigate the nature of their presence in Iranian waters.

Though there had been instances of confrontations between the IRGC and the US Navy prior to this incident, this was a significant moment given its proximity to Implementation Day and the pictures that were shown around the world of the US soldiers’ detention. It further drew attention to the existence of a working relationship between Secretary of State John Kerry and Foreign Minister Mohammad Javad Zarif, and their ability to get the incident quickly resolved.

In the last few years, there have been some other incidents at sea. For example, in 2007 Britain’s military service members were held for 13 days. In 2015, France and the US were on the receiving end of rockets launched by Iran in the Strait that reached within 1,500 yards of an American aircraft carrier.

Since then, naval incidents have continued, despite a temporary decrease in press coverage. For example, in September 2016, seven Iranian naval ships approached the USS Firebolt as it was operating through international waters, an action the US viewed as hostile.  Days later, the IRGC also threatened to shoot two American surveillance aircrafts flying close to Iranian airspace.

On March 21, 2017, the IRGC approached the aircraft carrier USS George H. W. Bush while it traveled through the Strait of Hormuz. Navy commanders called it harassment, as they were interrupted in navigating towards their destination.

More recently, on April 24, 2017 an IRGC vessel approached an American Navy destroyer despite the Navy’s efforts to communicate with the Iranians using bridge-to-bridge radio. The Americans sent an internationally recognized danger signal to warn against attack, but the Iranian vessel came within 1,100 yards of the destroyer and later turned to sail away without communication.


What are possible reasons for these naval incidents?

The US views Iranian actions in the Strait of Hormuz as improper and unsafe intercepts.  Some possible explanations as to why Iran may want to pursue an aggressive posture in the Strait include:

(a)   War games/ military practice: The IRGC has been conducting war games in the Strait since 2006 as a type of naval defense training. Because of the importance of the Persian Gulf and the Strait of Hormuz, particularly now that Iran is able to sell its oil to other nations and needs the Strait to remain open for oil transport, it may be conducting these exercises to ensure military control or defense capabilities.

(b)   Dissatisfaction with results of the nuclear deal: as JCPOA negotiations were coming to a close, Supreme Leader Khamenei was said to use the IRGC as a symbol of displeasure of Iran’s concessions. Therefore, aggressive postures at sea could be a signal regarding Iran’s status as a regional power and ambitions to operate the Persian Gulf as its own waters; or, it could be a message intended for domestic consumption, to show the Iranian people that they can stand up to the West.

Explanations like those above assume the American interpretation of Iranian aggression at sea. Another possibility may lie in a more mundane disagreement between the US and Iran about the applicability of maritime law:

The Strait of Hormuz is considered as a “strait used for international navigation” in the language of the 1982 UN Law of the Sea Convention (UNCLOS), to which Iran is a signatory. As a result, under UNCLOS, all states may navigate freely through the Straight via the legal term of “transit passage.” The law states that transit passage is legal and free, but it should be “expeditious and continuous, unless in case of force majeure.”

Iran declared when signing UNCLOS that all who were not party would fall under innocent passage.  Therefore, because the United States is not a party to UNCLOS, whenever its ships enter the 12 nautical mile radius off of Iranian shores under Iran’s control, it is therefore entering those waters under a different category called “innocent passage”, and not “transit passage” meaning that it must not be challenging the peace or security of the state in question.

According to Iran’s interpretation of the law, since the United States is not a party to UNCLOS, and is operating in the Straight via “innocent passage” they argue that the US must first ask for passage permission from Iran to transit the Straight, and that Iran is within its right to defend the 12 nautical mile radius off its shores from the US presence, which it views as conducting non-innocent passage. The US disagrees that it must ask permission or that it is conducting non-innocent passage.


What is Iran’s reaction to the naval incidents?

There is a notable silence from the politically elected branch of the Iranian government on this issue. The Iranian military, however, has responded to the American claims of harassment. On March 25th, Brigadier General Masoud Jazayeri stated that the claims of the US are "false reports or [have] ulterior motives". He also stated, "we emphasize that the Americans would be responsible for any unrest in the Persian Gulf, and again warn that the U.S. military must change its behavior."

On May 2nd 2016, Supreme Leader Ali Khamenei spoke out against the American presence in the Strait of Hormuz, saying the Americans should go back to the Bay of Pigs. He continued on to say that American drills in the Strait are a demonstration of hypocrisy since the US asks Iran not to hold war games there despite an active American presence.

Due to the frustrations of the US presence in the Strait, in 2016 Revolutionary Guard General Hossein Salami went as far as suggesting Iran would close the Strait unless the United States stopped “threatening” the area.

Fars News, the semi-official government news outlet, reports the incidents by citing Iran’s entitlement to police the waters of the Strait. It emphasizes that IRGC is simply there to defend its own waters. It also covers Iranian war games as ordinary, stating that “war-party Washington” is politicizing it to represent displeasure with the American administration.


What is the US government reaction?

In Congress, Randy Forbes of Virginia, Representative and chairman of the House Armed Services Seapower and Projection Forces Subcommittee, sponsored a bill on April 28th, 2016, stating that Iran was not abiding by UN maritime resolutions and international maritime laws, calling for a response to this dangerous behavior and for the House to consider Iran's actions when debating sanctions on the country.

While naval incidents increased under the Obama administration, no action for deterrence was taken. Now, under the Trump administration, naval incidents and increasing tensions are garnering closer scrutiny. As a candidate, Trump stated that if Iranian ships approached any more American ships, the Americans would be tasked with shooting them “out of the water”.

As President, Trump’s response has been to send the USS George H.W. Bush aircraft carrier to the Strait in March 2017. Lieutenant Ian McConnaughey stated, "[o]ur intention is never to start anything but if the situation arises, we are within our rights to defend ourselves."