For those of us who had hoped Defense Secretary Jim Mattis and Lt. Gen. H. R. McMaster, the president’s national security advisor, would make up for the inexperience and curb the impulses of the current administration, the last few weeks have been particularly discouraging. The unilateral missile attack on a Syrian airfield violated both international law and, in the view of many (including me), the Constitution. The net foreign policy value of that attack appears to have been negative—accomplishing nothing of lasting value in Syria and making our potential enemies more wary of American intentions. The threat of repeating these errors on a grander scale now looms with regard to North Korea. On Wednesday, the entire Senate will head to the White House for a briefing on North Korea with top administration officials. As Congress evaluates the information being provided by the executive branch, it must remember its role when it comes to involving the country in war. All elected and appointed officials should defend the Constitution and stand for the rule of law by demanding that the president not only consult Congress but also receive affirmative authorization to attack North Korea, should it become necessary.

A president does not have independent constitutional authority to initiate war with a foreign nation. The “limited” nature of the attack on Syria does not cure its constitutional defect. The result of using armed force against another nation is an armed conflict regulated by international laws of war. In Syria, the hostilities of the armed conflict that our attack created were limited only because Syria and its allies chose not to respond. Both Mattis and McMaster know, better than most, that the enemy gets a vote. Had Syria exercised its inherent right of self-defense, with Russia acting in collective self-defense, America might now be at war with two foreign powers without Congress having debated its wisdom or necessity, or putting the matter to a vote. That Syria and Russia “voted” as they did does not mean that the attack was constitutional. It means the US was fortunate that this hasty, unilateral decision did not have grave results (unless, perhaps, we knew how Russia would respond in advance).

Whatever constitutional authority exists for a president to use the military as an instrument of foreign affairs, it is limited by Congress’s express and plenary constitutional power to declare war. Of course, the Supreme Court has held that a president may act defensively and conduct initial hostilities without a declaration of war in response to an actual or imminent attack by an enemy. But that is the only clear exception to a constitutional separation of powers that requires the president to seek Congress’s affirmative approval rather than merely its acquiescence. (A less certain exception may be limited authority to enforce Security Council resolutions or to uphold affirmative treaty obligations.) The president certainly has the constitutional power and duty to defend the nation. A central purpose of the War Powers Resolution was to ensure that: 

The constitutional powers of the President as Commander-in-Chief to introduce United States Armed Forces into hostilities, or into situations where imminent involvement in hostilities is clearly indicated by the circumstances, are exercised only pursuant to (1) a declaration of war, (2) specific statutory authorization, or (3) a national emergency created by attack upon the United States, its territories or possessions, or its armed forces. 50 U.S.C. § 1541(c) (emphasis added)

The War Powers Resolution is not, and was never intended to be, a blank check for a president to use the armed forces for any reason or in any manner he thinks appropriate for up to 60 days. If that were the case, the War Powers Resolution would simply be unconstitutional.

The constitutional implications of attacking North Korea are profound. Were this president to act unilaterally against North Korea before it launched an attack upon either the Untied States or an ally, it would be a clear violation of both international law and likely the Constitution, the latter depending on the imminence of an attack by North Korea. This time, though, a regional war is more likely to result, and it would be one potentially involving nuclear weapons.

One might fairly argue that a president may, consistent with his constitutional powers and obligations, unilaterally order a preemptive, defensive strike against a foreign nation with the current capacity and a clear intention to launch a significant strike on U.S. vessels, troops, or territory. But that constitutional case depends on the actual existence of such a capacity and the intent to use it. There must be strong evidence that North Korea is preparing to launch a significant attack that is both intended to strike, and also capable of reaching, U.S. vessels, troops, or territory. Otherwise, there is no valid constitutional argument for a president’s power to unilaterally order a preemptive strike.

Some suggest that seeking affirmative congressional authorization will reveal our intentions and make any future strike less effective. That argument seems disingenuous at best and borders on being specious. The president has already threatened unilateral action and announced the dispatch of an “armada” to the region. If North Korea has not already prepared for an attack, it is not clear what express congressional authorization would add to its motivation to do so.

Given the likelihood North Korea has already prepared, preserving important constitutional principles and the rule of law is paramount. We must make every effort to maintain what Justice Robert Jackson called the Constitution’s “equilibrium.” Before taking military action that has the potential to start a regional or world war involving nuclear-armed nations, the people’s representatives in Congress must determine what is in the best interests of the country. To prevent disclosing the timing of any ultimate attack, Congress could grant conditional authorization for the president to use force, perhaps dependent upon exhausting specific diplomatic efforts. (Note: Article 1 of the 1907 Hague Convention Relative to the Opening of Hostilities required a “previous and explicit warning” and allowed an “ultimatum with conditional declaration of war.” Because declarations of war could be conditional, a conditional authorization to use military force would arguably be as consistent with the Declare War Clause as the unconditional 2001 and 2003 authorizations to use military force.) This would clarify American intentions in a way that is helpful to promoting a diplomatic solution without disclosing the fact or timing of an attack, should it become necessary.

Every government official involved in addressing this situation has taken an oath to support and defend the Constitution. The president’s oath is to “preserve, protect, and defend” the Constitution. He must also “take care that the laws be faithfully executed,” which includes the United Nations Charter. Unless it becomes clear that North Korea is about to launch a significant attack against American vessels, troops, or territory, supporting and defending the Constitution requires insisting upon congressional approval for any preemptive military strike.

Image: Chung Sung-Jun/Getty