The potential for the United States to stumble into a new war—or wars—has rarely been greater. Since before he took office, Donald Trump has been rattling his saber, and he is now backed up by a national security advisor who is openly spoiling for a fight. Instability and violence around the world are presenting them with ample opportunities. Last week marked the second time President Trump ordered bombings of Syria without congressional authorization.

Congress is now poised to bring a lit match to this combustible mix. A bill introduced yesterday by Sens. Bob Corker, R-Tenn., and Tim Kaine, D-Va., would give the president a virtual blank check to expand the current war against various terrorist groups to new enemies and new locations of the president’s choosing.

The professed intent of the bill is to reassert Congress’s authority over matters of war. Over the past 17 years, the war against Al Qaeda and the Taliban that Congress authorized in 2001 has metastasized into a seemingly permanent war against terrorist groups that did not even exist on 9/11. Congress has sat by and watched as presidents, first Barack Obama and now Donald Trump, have waged war against the Islamic State and other groups across the globe.

Senators Corker and Kaine want Congress to get back into the game. Unfortunately, however, their bill would do little more than codify Congress’s abdication. It would authorize the use of military force against the groups the United States is currently fighting, in the countries where we are fighting now. But it would not limit the conflict to those groups or countries.

Instead, the president could add new groups that he determined were “associated” with the listed groups. And while the bill would not authorize the president to add nation-states to the list, it would permit an easy runaround: by characterizing strikes on countries where terrorists operate — or like Iran, are designated as state sponsors of terrorism — as sanctioned attacks on terror groups.

If the president designated a new enemy group or theater of war, the bill would require him to report the expansion to congressional committees. The report could include a classified annex, which means that in practice, the president alone would decide how much information to make public. Congress would then have the opportunity to pass legislation disapproving the president’s action, presumably by a veto-proof margin.

Of course, Congress doesn’t need to give itself permission to pass a law. At any time in the past decade, for instance, legislators could have outlawed the use of military force against the Islamic State. The point is, they shouldn’t have to. Under the Constitution, war may be declared by Congress alone. The Corker-Kaine bill would flip this constitutional power on its head, assigning the president the role of declaring war against a given enemy in a given place, and leaving Congress only with the power to un-declare it.

Moreover, it’s a pipe dream to imagine such an undeclaration would ever occur. True, the bill would allow any lawmaker to force a floor vote, which would overcome a major procedural obstacle. But obtaining a veto-proof majority would be another matter. There is a big difference between failing to authorize the use of military force and voting to prohibit it. Congress has been doing the former for years; the latter would test the courage of most lawmakers. In practice, then, the bill would provide no meaningful limit on the groups with whom we would be at war or the places where we would be fighting.

Some lawmakers are ready to accept an ill-defined conflict if it is finite. As Senator Chris Murphy, D.-Conn., said, “I’m willing to have less tactical and geographic limitations as long as there is a sunset.” Every four years, the bill would require the president to submit a proposal to continue, modify, or repeal the authorization. A 60-day window would follow in which any lawmaker could force a vote, preceded by a strictly limited debate, on a single resolution to repeal or modify the law.

Here again, the bill gives the power to the president and then dares lawmakers to take it away. Congress tried something similar in 1976, in response to a proliferation of national emergencies declared by presidents over several decades. The National Emergencies Act authorized the president to declare emergencies, but instructed Congress to meet every six months to consider a vote on whether the state of emergency should be terminated.

Emergency declarations have been in place in each of the 40 years since that law took effect, which means Congress should have voted 80 times. It has not done so once. When a federal court examined this failure in the 1980s, then-judge (and current Supreme Court justice) Stephen Breyer ruled that the statutory requirement was better viewed as merely an option, enabling any member of Congress to force a vote. Over four decades, no member has ever chosen to exercise this option, let alone persuaded a veto-proof majority of Congress to go along.

There is little reason to expect a different outcome here. The power to wage war is an emergency power—perhaps the ultimate one. It enables the government to engage in a wide range of activities, both at home and abroad, that would be off-limits in peacetime—including using lethal force against U.S. citizens overseas or detaining them indefinitely without criminal charge.

Like all emergencies, war should be temporary, and the extraordinary powers extended to the government should go no further than necessary to address the crisis. But, as in all emergencies, it is both easier and politically safer for members of Congress to give the president unlimited leash. That way, if Americans later perceive that the government has not done enough to keep them safe, the blame will lie with the president and not the lawmaker.

Under the Corker-Kaine bill, the default is that the president determines the scope and length of the war. Only if Congress chooses to act in the future will there be any limits. That simply codifies, and thereby blesses, the decision-making framework we have today—a framework that subverts the Constitution’s allocation of powers and all but guarantees a forever war. Such license is dangerous enough under the best of circumstances. Under this president, it’s madness.

Sens. Corker and Kaine should go back to the drawing board. Any new authorization should specify who the enemy is and where the war is taking place. And because terrorist groups, unlike nation-states, will never formally acknowledge defeat, it should include a real sunset. If the war is still ongoing, Congress can reauthorize it; if, in the meantime, new enemies emerge in new places, Congress can pass another authorization. But endless war against nameless enemies should never be the default.