The “it” is the post‐​9/​11 Authorization for Use of Military Force resolution, or AUMF, adopted three days after the terror attacks, and now going on its lucky 13th year. It’s been in effect nearly twice as long as the Gulf of Tonkin resolution authorizing Vietnam, what was “America’s Longest War” — until the 21st century, that is.

On Sept. 14, 2001, Congress authorized the president to use “all necessary and appropriate force” against the perpetrators of the 9/11 attacks and those who “harbored” them. Two successive administrations have since turned the 60 words of the AUMF’s operative clause into what journalist Gregory Johnsen calls “the most dangerous sentence in U.S. history” — a writ for a war without temporal or spatial limits.

The last time the Senate held hearings on the AUMF, Sen. Lindsey Graham, R-S.C., asked the Pentagon’s civilian special operations chief, Michael Sheehan, “does [the president] have the authority to put boots on the ground in the Congo?” Answer: “Yes, sir, he does.”

Predictably, the hawkish Graham was totally okay with that. “The battlefield is wherever the enemy chooses to make it,” right? Right, said Sheehan: “from Boston to the [Federally Administered Tribal Areas of Pakistan].”

Asked how much longer the war on terrorism will last, Sheehan replied, “at least 10 to 20 years.” So presumably the AUMF can serve as the basis for Chelsea Clinton’s “kill list” in 2033, after she trounces George P. Bush.

Lyndon Johnson once compared the Gulf of Tonkin resolution to “Grandma’s nightshirt” because “it covers everything.” Even LBJ might have marveled at how the last two administrations have stretched the post‐​9/​11 AUMF.

Under the theory that “the United States is a battlefield in the war on terror,” the Bush administration invoked it to justify warrantless wiretapping and military detention of American citizens on American soil. The Obama administration cites it as legal authority for the extrajudicial killing of Americans via remote‐​control.

The Senate Foreign Relations Committee will be taking another look at the AUMF this week. The hearing’s title, “Authorization For Use Of Military Force After Iraq And Afghanistan,” hints at a preordained conclusion: that an updated authorization is needed. Ranking Republican Sen. Bob Corker of Tennessee wants to be sure the executive branch has “all the tools and capabilities” it needs to address “threats that did not exist in 2001.”

Rep. Barbara Lee, D‐​Calif., the sole member of Congress to vote “no” on the original AUMF, has a better idea: end it, don’t mend it. Joined by libertarian‐​leaning, antiwar Republicans like Reps. Justin Amash and Walter Jones, she’s introduced legislation to repeal the AUMF.

Two imperial presidents in a row have treated that authorization like a permanent delegation of congressional war power to the president. Their successors would no doubt do the same with any new “tools and capabilities” they’re given.

Without the AUMF, presidents still retain the constitutional power to “repel sudden attacks,” as James Madison put it. And if they think groups like al‐​Shabaab or Boko Haram demand a more sustained military response, they’ll be free to make that case to Congress. But delegating new authorities in advance might permanently change our constitutional default setting from peace to war.

Madison also said that “No nation could preserve its freedom in the midst of continual warfare.” We’re now into our second decade running that experiment; how much longer do we want to risk proving him right?