The U.S. military should view the recent quiet as a short-term interlude in Tehran's longstanding doctrine of aggressive naval behavior.
On January 26, the Wall Street Journal reported a near total cessation of small-boat harassment actions by the Islamic Revolutionary Guard Corps Navy (IRGCN) over the preceding five months, according to U.S. military sources. This shift has led many observers to speculate about Iran's potential motives, which could include a change in naval doctrine, a switch in tactics, or increased caution in the face of tougher U.S. policies toward Iran. Whatever may be driving it, the reduction in naval harassment is unlikely to presage a permanent shift to a less aggressive posture, especially given Iran's track record in the Gulf and the IRGC's ideological pillars.
A PATTERN OF HARASSMENT
Since the early 1980s, the IRGCN's aggressive activities in the Persian Gulf and Strait of Hormuz have earned it a high-risk reputation with the U.S. Navy. According to American military officials, the monthly average for "unsafe and unprofessional" IRGC naval actions was 1.75 in 2015, 3.0 in 2016, and 2.0 over the first seven months of 2017. The IRGCN's recklessness is particularly salient when one considers that the regular Islamic Republic of Iran Navy (IRIN) has sent fifty task groups to the Gulf of Aden and Indian Ocean since 2009 without any known incidents involving U.S. vessels.
In contrast, the IRGCN often operates close to American ships in the confined waters of the Persian Gulf. Over the years, such tactics have caused numerous confrontations aimed at satisfying Supreme Leader Ali Khamenei's desire to badger and humiliate the American "enemy," ignoring the risk of escalation in the process.
DOCTRINAL OR TACTICAL CHANGE?
Since mid-August 2017, however, the average number of "unsafe and unprofessional" Iranian naval encounters has dropped to zero. One theory behind this puzzling change is that the IRGCN is simply "mixing it up" to avoid predictability and add an element of uncertainty to the Gulf equation. Khamenei has repeatedly defined "guardianship of the revolution" as a continuum that can take many forms depending on current "necessities." These forms extend well beyond mere protection of the region's military status quo—rather, he has instructed the IRGC to adopt creative, "non-conservative" approaches to planning and operations.
IRGC chief Mohammad Ali Jafari reiterated this view in a speech on January 30, 2017, outlining two seemingly different options for his organization to "defend the revolution": conservative defense of established revolutionary principles, and unconventional defense of the revolution's "dynamic movement forward." He then noted that the IRGC strongly prefers the second option. As for what that option actually means in practice, Jafari had offered a clue on March 18, 2014, when he delivered a speech declaring that the IRGC's very survival depended on timely "revolutionary actions" such as the periodic seizure of Western sailors in the Gulf (the last such episode occurred two years ago). Maj. Gen. Mohammad Bagheri, the head of Iran's Armed Forces General Staff, echoed Jafari's preference in a message released April 29, 2017.
In other words, a permanent cessation of IRGCN harassment tactics would represent a sharp divergence from the doctrine put forth by both Khamenei and the IRGC's senior leadership. It would also imply that the IRGC is foregoing the aggressive offensive posture upon which its institutional psyche is grounded at the strategic level.
Another possible explanation is that the IRGCN may be shifting to new tactics or platforms, such as decreased reliance on small-boat swarm attacks and increased reliance on drones and submersibles. On January 12, 2016—the same day ten U.S. sailors were captured after straying into Iranian waters—an unarmed Shahed 129 drone flew over the American aircraft carrier USS Truman and the French carrier Charles de Gaulle in the Persian Gulf. It was reportedly the first such overflight in two years. Yet these rare incidents soon became daily occurrences, aided by the increased availability of more-capable long-endurance drone designs. Most notably, Iranian drones engaged in dangerous encounters with aircraft from the USS Nimitz in August 2017.
NEW CAUTION TOWARD THE UNITED STATES?
Another possibility is that the IRGCN is deliberately behaving more carefully around U.S. vessels, whether due to pressure from the Rouhani government or the IRGC's calculations about Washington's intentions. During his presidential campaign, Donald Trump repeatedly condemned the IRGC's Gulf intimidation tactics, promising that Iran's "little boats...will be shot out of the water" if they continue making improper "gestures" at U.S. vessels.
Yet the IRGCN did not appear to change its behavior immediately after Trump took office: the first half of 2017 saw at least fourteen "unsafe and/or unprofessional interactions" between U.S. and Iranian naval forces, compared to thirty-six in all of 2016. Last June and July, IRGCN boats harassed American vessels in at least two cases, while Iranian drones flew dangerously close to the USS Nimitz or its landing aircraft twice in August. Later that month, however, U.S. military officials report that such behavior suddenly stopped.
This suggests that something might have changed in the IRGCN's calculations last summer. Iranian military officials claim that a "more professional" U.S. Navy posture was responsible for the drop in unsafe encounters, but there has been no apparent change in how American naval forces operate in the Gulf. Perhaps firmer U.S. military actions elsewhere in the region were a factor, including the cruise missile strike on al-Shayrat Air Base in Syria (April 7, 2017), assorted airstrikes on pro-Iranian militias in Syria (May 18, June 6, and June 8), the shootdown of Iranian drones in Syria (June 8 and June 20), and the shootdown of a Syrian jet (June 18). Moreover, July 2017 was when the Trump administration gave the strongest signals yet that Washington might not recertify the Iran nuclear deal when it came up for review that October.
The possibility that the IRGC might change its behavior in response to outside pressure should not be discounted, since the organization has previously been compelled to hold back on other fronts. For example, some aspects of its long-range missile program have been hindered by political, if not budgetary, issues for some time, with conservatives accusing the Rouhani government of withholding funding from the Defense Ministry's space launch program for the third consecutive year—likely due in part to pressure from Washington and its allies.
The IRGCN should therefore be encouraged to continue its de-escalatory behavior. To boost the prospects that this improved posture will become the future standard, the U.S. Navy should not only highlight periods of calm, but also publish details of any "unsafe and unprofessional" encounters as soon as they occur. By sharing the details with international organizations, maritime safety bodies, and the public, Washington can help increase the diplomatic price Iran pays for such activities.
At the same time, however, coalition forces should not let their guard down, since the IRGC has shown that it can change its Gulf tactics quickly. While the IRGCN retains some flexibility in rearranging its "first line of defense" along Iran's maritime borders, its doctrinal preference remains the type of aggressive "revolutionary action" defined by the Supreme Leader.
Farzin Nadimi is a Washington-based analyst specializing in the security and defense affairs of Iran and the Persian Gulf region.