Congress could overturn the 9/11 law authorizing ever-expanding war

A Navy SEAL, killed alongside civilians in a January raid on a village in Yemen. Another SEAL, killed while accompanying Somali forces on a May raid. And now four Army soldiers, dead in an ambush this month in Niger.

These US combat deaths — along with those of about 10 service members killed this year in Afghanistan and Iraq — underscore how a law passed shortly after the Sept. 11, 2001 terrorist attacks has been stretched to permit open-ended warfare against Islamic militant groups scattered across the Muslim world.

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The law, commonly called the AUMF, on its face provided congressional authorization to use military force only against nations, groups, or individuals responsible for the attacks. But while the specific enemy lawmakers were thinking about in September 2001 was the original al-Qaeda and its Taliban host in Afghanistan, three presidents of both parties have since invoked the 9/11 war authority to justify battle against Islamic militants in many other places.

On Oct. 30, Defense Secretary Jim Mattis and Secretary of State Rex Tillerson will testify before the Senate Foreign Relations Committee as lawmakers renew a debate over whether they should update and replace that law, revitalizing Congress' constitutionally assigned role of making fundamental decisions about going to war.

But even as President Donald Trump's administration moves to ease some Obama-era constraints on counter-terrorism operations, political obstacles to reaching a consensus on new parameters for a war authorization law look more daunting than ever.

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Previous efforts collapsed under disagreements between lawmakers opposed to restricting the executive branch's interpretation of its wartime powers and those unwilling to vote for a new blank check for a forever war. Among the disputes: whether a replacement should have an expiration date, constrain the use of ground forces, limit the war's geographic scope, and permit the government to start attacking other militant groups merely associated with the major enemies it would name.

Adding to the political headwinds, two of the Republican lawmakers most interested in drafting a new war authorization law are lame ducks and estranged from the White House: Sen. Bob Corker of Tennessee, who is chairman of the Foreign Relations Committee, and Sen. Jeff Flake of Arizona, who has proposed a new war authorization bill with Sen. Tim Kaine, D- Va. Both Republican senators, who have announced that they will not seek re-election, have publicly denounced Trump in recent weeks as dangerously unfit to be the commander in chief.

But as the 9/11 war enters its 17th year, questions about the scope and limits of presidential war-making powers are taking on new urgency.

Trump is giving the Pentagon and the CIA broader latitude to pursue counter-terrorism drone strikes and commando raids away from traditional battlefields. Two government officials said Trump had recently signed his new rules for such kill-or-capture counter-terrorism operations, without major changes to an inter-agency agreement first described last month by The New York Times.