Iran’s conventional Navy, known by its Persian acronym NEDAJA, reportedly deployed two vessels to international waters surrounding Yemen yesterday. First reported in the semi-official Iranian press, the story has also been noted in the Western press, where it was framed as part of the larger Saudi-Iranian rivalry, and the ongoing war in Yemen.

The official Iranian motivation behind the deployment of the 44th Naval Flotilla – which consists of one frigate (the Alvand) and one logistics/support vessel (the Bushehr) – is to deter piracy and defend trade. However, this deployment to the Bab al-Mandeb Strait, which is a strategic chokepoint where over 3 million barrels of oil pass per day, comes amid an intensification of the war in Yemen. Most recently, the US has taken to responding to attacks on its military vessels in the region. Yesterday, the US responded with Tomahawk missile strikes against three coastal radar systems in Houthi-controlled territory. It remains unclear if these strikes will sufficiently deter future attacks. Some defense analysts have even alluded to the radar sites being previously rendered un-operational.

The attack followed two separate occasions where anti-ship missiles were fired from Houthi-controlled territory at vessels linked to the coalition. On Oct. 1, Houthi rebels fired an anti-ship missile (likely a C-801 or C-802) at a United Arab Emirates logistics vessel on the Red Sea. That was followed by a thwarted missile attack on an American vessel in the Red Sea on Oct. 9.

Iran has deployed naval flotillas from its conventional naval warfare fleet numerous times in the past. Often, these are trips to showcase a new vessel, or to dock in welcoming ports as a symbol of friendship. This flotilla deployment, however, appears to be aimed at sending a signal to the U.S. as well as the Saudi-led military coalition about Iranian resolve. In the past, Iran has promised retaliation and even “war” should its humanitarian vessels in Yemen be targeted. In fact, the Alvand is no stranger to confrontations with the US Navy, aiming its guns at an American MH-60R Seahawk helicopter and coalition auxiliary ship operating in the same waters in July 2015. It remains to be seen if they will make the same threat here.

A Growing Pattern of Maritime Misbehavior

This deployment by Iran appears to be more posturing than an attempt to actually clash with the US Navy. The 40-year-old Alvand, armed with C-802 missiles but lacking modern radars and defensive systems, would have little chance of surviving a skirmish against the larger and more advanced American destroyers (USS Mason and USS Nitze). As the Mason proved earlier this week, US countermeasures can easily thwart attacks from missiles similar to the Alvand’s and the appearance of Iranian vessels is unlikely to provoke a significant reaction from the US.

If a confrontation were to occur it would be a continuation of Tehran’s growing pattern of aggressive maritime behavior towards western vessels operating in the region this year. In August, Iranian craft harassed American warships on four different occasions in the span of a week, with one incident requiring the USS Squal, a Cyclone-class patrol boat, to fire warning shots in response. In a more serious incident in January, Iranian forces seized ten US sailors when their riverine patrol boats drifted into Iranian waters in the Persian Gulf. The dramatic images and videos of the crew in Iranian custody have been repeatedly used by Iranian media outlets for propaganda purposes and reports suggest the sailors disclosed sensitive information while at gunpoint. That incident came just days after members of the Islamic Revolutionary Guard Corps’ Navy fired rockets near the aircraft carrier USS Harry S. Truman as it transited the Strait of Hormuz.

The purpose of increased maritime confrontations appears to be a desire to project Iranian moxie and capability against its enemies amidst conventional military weakness. While the deployment of the Alvand and Bushehr are likely a continuation of that effort, it could have the dual purpose of reassuring Tehran’s Houthi allies.

Patrick Megahan is a Research Analyst focusing on military affairs at Foundation for Defense of Democracies (FDD), where Behnam Ben Taleblu is a Senior Iran Analyst.

This article originally appeared in The Long War Journal.