A patriotic president who can legally justify acting against our enemies will be obliged to take actions if those actions seem both prudent and necessary.

Here we go again: The president has committed an act of war without Congress declaring war against that enemy. The use of lethal military force abroad against a foreign enemy is by definition an act of war, and using euphemisms to describe it otherwise does not change that fact. An act of war is also an act of war whether or not the other guy is already at war with you. This is not how our system is supposed to work. It is, however, how our system does work in the 21st century. A president who waits by the phone for Congress may never be able to do anything. And therein lies a dilemma for constitutionalists — because the president is supposed to be an energetic defender of the nation.

The United States has fought a declared war only five times in its history: the War of 1812, the Mexican War, the Spanish-American War, the First World War, and the Second World War. (There have been eleven declarations of war, but only because Congress voted to declare war on multiple enemies separately in the two world wars). Presidents have committed acts of war many more times than that. Even leaving aside dozens of armed conflicts with Native American tribes inside the territorial United States since 1789, we’ve sent armed men to fight by land, sea, and/or air without a formal declaration of war in (among other places) the Barbary States, Korea (at least twice, the first in 1871), Iraq (at least twice), Vietnam, Afghanistan, Russia (in 1918), Japan (in 1864), China (in 1900), Mexico (in 1914), Nicaragua (against Britain in 1854), Panama (in 1903 and 1989), Kosovo, the Philippines, Libya (in 1985 and 2011), Grenada, Syria, Niger, the Dominican Republic (in 1916 and 1965), Samoa (in 1899), Cambodia (in 1975), Pakistan (in 2011), and Haiti (in 1915). It was a de facto act of war, and surely a just one, when Jimmy Carter sent American armed forces into Iran to try to rescue the hostages. I’m sure I’m missing more than a few examples, to say nothing of “peacekeeping” efforts such as Somalia in 1992 and Lebanon in 1983 that nominally avoided taking sides but inevitably involved combat. Some of these deployments were by air or sea only; some were explicitly permitted by a congressional authorization of military force before or after the fact; some were implicitly ratified when Congress provided funds or other support without voting on the use of force; some arguably involved responses to ongoing or imminent attacks, some were punitive or retaliatory, and some were effectively preemptive. A full review of the precedents would be extensive and defies doctrinal consistency.

Charlie and Andy have been conducting a spirited debate the past week on whether President Trump had the constitutional authority to bomb Iran without prior approval from Congress. You can read Charlie’s “no” case here and here, Andy’s “yes” case here, here, and here, and watch their debate here. Charlie is right on the general point that the constitutional design is supposed to involve Congress before the fact in making decisions to commit acts of war, given its Article I, Section 8 power “to declare War [and] grant Letters of Marque and Reprisal,” the latter of which entails authorizing private parties to make war on behalf of the nation. The Framers of the Constitution understood that presidents would at times need to act without that approval to deal with urgent threats, but they expected this to be the exception rather than the rule. The Senate was also given power to ratify treaties, which was expected to involve one house of Congress in deciding when a war ends, and on what terms.

In the case of bombing Iran, speed and secrecy were important, and we were time-pressured because Israel had already commenced a bombing campaign against the Iranian nuclear program without waiting for us (and arguably with the intent of forcing our hand). But Trump could have asked Congress to proceed swiftly to a vote after a few days’ debate on an authorization to use force specific to this enemy and to the war aim of destroying its nuclear-enrichment and missile-building efforts. Doing so undoubtedly would have been the better constitutional and civic practice, and would save Trump from headaches he may yet face down the road by getting legislative buy-in up front. George W. Bush’s administration, as much as it resisted arguments that it constitutionally needed advance approval, nonetheless benefited significantly from getting Congress to approve in advance war in both Afghanistan and Iraq. Fundamentally, Trump decided to open a new chapter in our response to Iran’s long-running wars against the United States and Israel, not merely to preempt an immediate attack. In a properly functioning constitutional system, that should be the subject of a new vote by Congress.

That said, Andy makes the case that the pre-existing AUMFs — now a quarter of a century old — are so broad that they probably authorize this campaign. That’s a good reason why a Congress that takes seriously its role in the constitutional structure ought to repeal them and insist on a new AUMF for anything of this scale. But it was clear enough that Congress was not exactly champing at the bit to vote on this rather than letting the president take the lead, the credit, and the blame. Congress is too busy not passing budgets and not making laws. Constitutionalists who want to fault Trump should recognize not only that he’s walking the same path we’ve long accepted in practice, but also that he has an arguable legal leg to stand on.

Which brings us to what a responsible constitutionalist executive should do when Congress is basically asleep at the switch and uninterested in doing its job. While the legal justification is somewhat thin, the president does have inherent Article II powers and duties in foreign affairs and in the use of the military that he does not have in domestic legislation. His very first enumerated power in Article II is, “The President shall be Commander in Chief of the Army and Navy of the United States, and of the Militia of the several States, when called into the actual Service of the United States.” The Senate may ratify treaties, but the president makes them. Thus, both the conduct of war and the ending of war are squarely within his powers.

Constitutionalists have often and rightly criticized the “pen and phone” executive fiat approach of Presidents Obama and Biden (of which Trump has not always been innocent) to using administrative rulemaking and executive orders to effectively make legislation when Congress won’t act. While presidential war powers present their own issues of an imperial executive, however, there’s a fundamental structural difference between the Article I legislative powers of Congress — which the president can exercise, at most, only in very limited delegated ways — and the Article II executive powers, which have independent force. Presidents have no inherent power to legislate. At most, they can issue regulations to fill in the details of laws that Congress has already enacted, and even then, there is much controversy about how much of that power Congress may delegate to the executive.

The warmaking power, however, is just categorically a different question than something like, “Can the president issue debt without Congress?” or, “Can the president order workers to take a vaccine without Congress?” He cannot do those things, full stop. They are by nature legislative, not executive, acts. The Article II commander in chief power, however, is designed to permit some ambiguity in how the president may act with dispatch when Congress is silent, because Congress may be unavailable. The early Congresses were typically out of session for the first nine months of a president’s term, during which a lot could happen.

We’re in this fix because Congress stopped doing its job. Congress should vote on things like this, as it did in 2001-02. But the president has responsibilities for national security that do not disappear when Congress does. When Congress won’t act, that gives presidents no additional power to act as lawmaker. But somebody still has to protect the nation against foreign enemies, and the guy sworn and constitutionally armed to do so has something more of an argument from necessity in that situation, not for bulldozing the prerogatives of Congress but for working as far within the margins as he can. In the design of the American system, the default is that if Congress fails to legislate, the state legislatures take over. That doesn’t work perfectly in areas that require national lawmaking (such as immigration), but it’s the nature of the system. If power is not exercised in Washington, it devolves on state capitals, or ultimately upon the free citizenry.

But in international affairs, if the president doesn’t act, power doesn’t shift to the states, but to foreign capitals. That puts presidents in a serious bind when Congress is asleep at the switch, as it increasingly has been for decades. A patriotic president who can legally justify acting against our enemies, however strong his or her attachment to the Constitution, will be obliged to take actions if those actions seem both prudent and necessary.