Yesterday’s small boat swarm attack on a Saudi frigate operating off the coast of Yemen is thought to have been intended for a U.S. vessel instead, according to a recent report. Fox News states that U.S. intelligence officials believe the Iranian-backed Houthi rebels who executed the attack either believed the ship was an American surface combatant—and were attempting to inflict damage similar to that done by the explosives-laden small boat driven by a suicide bomber during the attack on the USS Cole—or it was a dress rehearsal in preparation for doing so.

The report references the fact that the cameraman was chanting “Death to America” during the short video sequence, posted online yesterday, showing the strike. It should be noted that the tracks on videos such as these are often dubbed, but regardless, it’s being viewed as evidence that raises the possibility the suicide bomber and the two other boats that swarmed the al Madinah-class frigate thought they were targeting a U.S. Navy warship. During the attack, the bomber detonated his craft near the frigate’s stern, killing two sailors and injuring three more. The ship is said to still be in semi-operational condition.

Although the report seems compelling, its claim that the operation may have been a “dress rehearsal” is highly questionable, considering that it was actually carried out in full. Also, there are large differences between the attack on the USS Cole and yesterday’s suicide bombing of the Saudi frigate—the biggest being that the Cole was at anchor making a refueling stop off Yemen’s southern port of Aden when the attack occurred some 17 years ago. As a result of the blast that killed 17 and injured 39 American sailors, large changes in force protection procedures were put into place across the U.S. Navy, and the threat from small craft, while underway or otherwise, remains one that the US Navy continues to grapple with to this very day.

Yesterday’s attack was a classic swarming small boat operation. These have been used before for harassment purposes in the Southern Red Sea near the Mandeb Strait. It is also a common tactic of Iranian forces operating in the Persian Gulf, especially near the Strait of Hormuz.

Tensions with Iran have ratcheted up since the election of Donald Trump, who has had strong messages about the Iranians and his distaste for the P5+1 nuclear deal. The Iranians just tested another ballistic missile, defying UN resolutions. It is fairly predictable that the Iranians will continue to test any new President, but if yesterday’s suicide attack had occurred on a U.S. ship, whether Iran had anything to do with ordering it or not, the outcome could be devastating for both the stability of the region and the world’s energy markets.

Just as Iran’s involvement in the Yemeni civil war became clear, I postulated the possibility of Tehran’s greater strategy, which may include the gaining the ability to shut down two of the world’s most strategic maritime choke points—the Strait of Hormuz and the Mandeb Strait—on a whim. Read all about this possibility and its potential repercussions in this past feature of mine. In it, I specifically talk about swarming boat attacks and the destabilization of the security situation in the southern Red Sea as being used as military tactics, leverage, and as a deterrent by Tehran. The fact that Iran seems to be quite interested in a more formal naval presence in Yemen simply lends more evidence to this possibility.

The Fox News report does not provide enough evidence to conclude the Houthi rebels were targeting an American Navy vessel and instead hit a Saudi one by mistake. The rebels arguably have more reasons to attack a Saudi-flagged surface combatant than an American one, considering the Saudis are leading a large group of Arab gulf states in the bloody war against them. The attack also comes at a time when tensions between Iran and Saudi Arabia are soaring.

Among all this uncertainty, one thing is for sure: the stakes have been raised for ships transiting through the Southern Red Sea. Now, the question is: how will Saudi Arabia respond—and who against?