Beto O’Rourke’s criticisms of U.S. foreign policy don’t get as much attention as those of his fellow Democratic presidential candidates Bernie Sanders and Tulsi Gabbard. But in a recent interview with The Nation, the former Texas congressman makes a point of listing several U.S. interventions that didn’t go well. “Look at [the 1953 CIA-orchestrated overthrow of Mohammad] Mosaddegh in Iran,” O’Rourke says. “Coming on 19 years in Afghanistan. Twenty-seven years in Iraq, [five] successive presidential administrations. Tell me that any of those wars or covert actions or interventions have made those countries, the world, or our foreign-policy prospects any better. They haven’t.”

Twenty-seven years isn’t the right year count for America’s presence in Iraq—more on that here—but the underlying point is valid. O’Rourke’s criticism of the Afghan intervention is especially welcome. The U.S. has lost 2,400 American lives and $900 billion in that war, yet Afghanistan faces worsening violence and instability.

The key to avoiding these types of conflicts “is to lead with diplomacy, holding the card of military involvement as the last resort,” argues O’Rourke. “We need to bring these wars to a close. We need to follow the lead of [Democratic Reps.] Mark Pocan (Wis.) and Ro Khanna (Calif.), who are trying to prevent us from going into new wars or continuing the wars that we are effectively in, in places like Yemen,” he tells The Nation.

Pocan and Khanna have been vocal opponents of U.S. involvement in the Yemen war. They were among the members of Congress to cosponsor legislation, which has now passed both houses of Congress, that tries to ensure that the president only commits U.S. military forces to conflicts abroad if he has congressional approval.

“This country has completely forgotten its constitutional responsibility to lawfully declare and end these wars, as prescribed in the first article of the U.S. Constitution,” O’Rourke tells The Nation. “I don’t think there’s been a meaningful vote on the wars since 9/11, since the ones we had in 2001 and 2002, and I think that’s desperately needed right now.”

O’Rourke is referring to a pair of congressional resolutions that easily passed in the aftermath of the 9/11 terror attacks. The 2001 Authorization for Use of Military Force (AUMF) gives the president power to take military action against any nation or person he believes to have been involved in the 9/11 attacks. It’s been used to justify military intervention not only in Afghanistan but in Syria, Somalia, the Philippines, and Niger. The 2002 Authorization of for Use of Military Force Against Iraq Resolution, meanwhile, allowed the U.S. to invade Iraq.

Some in Congress have tried to address this issue. Last month, for instance, Sens. Rand Paul (R–Ky.) and Tom Udall (D–N.M.) introduced legislation that would withdraw U.S. troops from Afghanistan and repeal the AUMF. The AFGHAN Service Act has yet to gain much traction the Senate.

In decrying unauthorized U.S. intervention abroad, O’Rourke echoed Paul, who warned Secretary of State Mike Pompeo last week that wars must be approved by Congress. “You do not have the permission of Congress to go to war in Iran. If you want a war in Iran, you have to come to us. It’s the way the Constitution was written, and it needs to be very clear,” the senator told Pompeo, who was testifying before the Senate Foreign Relations Committee.

Paul was specifically addressing a possible U.S. intervention in Iran, but the concept applies to other potential conflicts too: If the president wants to go to war, he needs congressional approval.

This sort of anti-interventionist sentiment is not unusual for O’Rourke, who has criticized Washington’s intervention in Iraq and Syria and has rightly called the AUMF “a blank check for endless war.” O’Rourke has come under fire from some on the left for not being progressive enough, but when it comes to foreign policy, he’s at least as much of an anti-war candidate as Sanders.