“A decade of war is now ending,” proclaimed the American president — eight years ago. President Barack Obama would soon expand what he had criticized as “a perpetual war,” the military conflict against Islamist terrorists that began in 2001 in Afghanistan but that sprawled to the war in Iraq and to many new enemies in many countries.

Now President Biden, too, is holding out the possibility of “ending the forever wars” by asking Congress to replace the 2001 and 2002 statutes that authorized wars against the 9/11 perpetrators and Iraq with a “narrow and specific framework.” Congress should embrace his worthy aspiration, but no one should be fooled. The president and Congress will need to go well beyond merely narrowing Congress’s old permission slips for war. That would leave the permanent war footing intact and preserve the president’s now almost limitless powers to fight anywhere, indefinitely.

To understand the limited significance of this approach to ending the forever wars, you need look no further than Mr. Biden’s Feb. 25 airstrikes in eastern Syria against the Iran-backed militias responsible for assaults on U.S. and allied personnel in Iraq. The United States is not at war with Syria or Iran, and Congress had not authorized the strikes. The president ordered them nonetheless, based on his independent authority, under Article II of the Constitution, “to conduct United States foreign relations and as Commander in Chief and Chief Executive.” Narrowing the 2001 and 2002 laws would leave this presidential power untouched.

The theory behind the Syria strike is that Article II allows the president, without congressional approval, to engage in what has been called “light-footprint” warfare — airstrikes (drone and manned), cruise missiles, cyberattacks and stealthy actions by Special Operations forces — in contexts that serve “the national interest.” Executive branch lawyers have interpreted the national interest to cover any conceivable situation in which a president, in the name of self-defense or a related rationale, would want to strike anywhere around the globe against even dim terrorist threats to the United States or its allies. They have gone further still to justify presidential unilateralism to mitigate humanitarian crises, to support international organizations and to preserve regional stability. And they have given presidents permission to ignore the constraints of the U.N. Charter.