The recent decision by President Trump to withdraw troops that protect U.S. ally Kurdish fighters has been argued to be an abandonment of these fighters and their families to our foes, including Iran of the willingness to protect basic interests in the region. If Iran interprets this action as a green light to resume harassment of vessels in the Strait of Hormuz, Congress will need to reopen debates whether or not to restrict President Trump from going to war with Iran without congressional approval. However, there is one aspect of the potential reopened conflict, seizures of oil tankers along with attacks on tankers in the Strait of Hormuz, that Congress has already given the President authority to intervene, militarily. Federal statutory law authorizes the President to employ naval forces "as in his judgment" may require to protect U.S. vessels against piratical aggressions and depredations. Piracy is an international crime and the normal rules for limited criminal jurisdiction do not apply. Consequently, U.S. warships can stop attack and take into custody crew members of pirate ships and the Department of Justice can prosecute captured crew members suspected of piracy in an American Federal court.
In the case where history repeats itself, the modern-day acts of violence in the Strait of Hormuz by Iran nationals is reminiscent of the Tripoli pirates in the early 1800s. Kilmeade and Yaeger in their bestselling book, Thomas Jefferson and the Tripoli Pirates, summarize the conflict and Jefferson's belief that he needed congressional approval to wage war against the pirates that cruise the Mediterranean seizing merchant ships and taking hostages. Congress, instead of making a declaration of war, gave President Jefferson extensive power to use the Navy to combat pirates, enacting laws that allowed for military action, as well as criminal statutes, to prosecute and punish captured pirates who were brought to American courts. These laws are clearly authorized by Article I of the Constitution that grants Congress the power to define and punish "Piracies ... and Offences against the Law of NationsP. Additionally in the War Powers clause Congress is also granted power to develop rules concerning "Captures on Land and Water". A recent example of the use of the Navy and the subsequent prosecution of pirates invoking these laws involved Somalia pirates who imprudently attacked the USS Nicholas and ended up with life sentences.
Where the Iran conflict gets tricky is that piracy is defined as "illegal acts of violence or any act of depredation committed for private ends" by crew members of a private ship. Iran, in order to gain political cover, describes some of the vessels attacking oil tankers as private vessels even though, apparently, they are crewed by Iranian military or paramilitary personnel. Other instances of vessel seizures are not as subtle with Iranian commandos rappelling from a helicopter on to a British-flagged tanker. However, since the federal statute that provided President Jefferson the ability to combat Barbary Coast pirates who worked hand in hand with those foreign governments that were extorting America in the early 1800s is accepted by legal scholars as an appropriate use of executive power, Jefferson's actions would be relevant to combating "Iranian pirates" in the present-day conflict. Indeed an argument can be made that the nature of the acts if they are not actions of war, are dispositive of piratical acts. The President, the argument goes, would merely be using his judgment to protect vessels of the United States from "piratical aggressions and depredations". Additionally, even though there was no air power available to President Jefferson, modern public armed vessels include aircraft carriers. As the statute authorizing judgment calls taken by the President regarding naval power to combat "piratical aggressions" is not limited to actions taken on the high seas; the executive branch has arguably more flexibility in extending military action than our third President had in his toolkit to combat the acts of aggression by Barbary pirates.
It is not the intent of this article to suggest that current law gives the present administration unfettered power to wage a war with Iran. However, at least in regards to attacks on merchant vessels in the Strait of Hormuz that arguably threaten U.S. vessels, Congress has already given the President authorization to act in a limited manner consistent with his judgment. Generically, judgment calls in the eyes of the law are normally questioned only if an abuse of discretion is proven, a very high bar indeed. This potential conflict may present the rare case where this President, who normally feels free to act without lawful authority, actually has the authority to do something Congress may want to restrict.
David W. Tiffany J.D., LL.M Admiralty
Adjunct Professor California State University San Marcos, retired