After President Trump ordered the US military to launch a strike on the Syrian airbase where this week’s sarin gas attack originated, many on the internet are claiming that he violated his constitutional authority as president. Only Congress can declare war, they say, so President Trump should have obtained a congressional authorization to launch his punitive attack.

This argument is based on a misunderstanding of the Constitution. While it is true that Article I Section 8 says that “The Congress shall have Power… To declare War, grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water,” the focus should be on what the Constitution does not say.

For example, the Constitution does not say that the president, who it names as the “Commander in Chief of the Army and Navy of the United States,” shall obtain the permission of Congress before deploying the army and navy in combat. The Constitution also does not say that a declaration of war is required before ordering the military to attack.

That the president has the power to order the military into combat unilaterally is not a recent interpretation of the original intent of the Framers. In his excellent book, “The Savage Wars of Peace,” Max Boot details the numerous small, undeclared wars and military actions that the United States has been involved in during our short time on earth.

Proponents of declarations of war might be surprised to learn that America’s first undeclared war occurred in 1801, a scant 14 years after the Constitution was ratified. Although Congress authorized action against Tripoli in 1802, a formal declaration of war against the pirate kingdoms did not come until 1815 under James Madison. Yet if President Jefferson overstepped his constitutional authority in ordering the US Navy and Marines to go to war against the kingdoms of the Barbary coast in what is now Libya, there would have been opposition from the still-living Framers of the Constitution and authors of the Federalist Papers. Jefferson’s opponents criticized his Louisiana Purchase as exceeding his authority instead.

Although the US has been involved in many conflicts, only five wars have been formally declared. These include the War of 1812, The Mexican War, The Spanish-American War, World War I and World War II. That does not mean that all other conflicts were unconstitutional, however.

Congress has authorized the use of military force at least 13 times without declaring war. The first such authorization occurred even before the Barbary wars when Congress authorized John Adams to use military force against France during the Quasi War of 1798-1800. Congress has authorized the president to use military force many times in recent years including in Vietnam, Afghanistan, and twice in Iraq. These authorizations could be construed to fill the constitutional role of a declaration of war.