WASHINGTON (Reuters) - The U.S. Congress is voting this week on legislation to repeal the 1991 and 2002 Authorizations for the Use of Military Force, or AUMFs, against Iraq, lawmakers' latest attempt to reassert Congress' role in deciding whether to send troops into combat.
Here is what to know about these war authorizations.
WHAT IS AN AUMF?
Under the Constitution, Congress, not the president, has the right to declare war. But to allow a president to respond to a threat, the Senate and House of Representatives can pass an AUMF.
The two that may be repealed this year were approved in 1991 after Iraq invaded Kuwait and in 2002, ahead of the 2003 U.S. invasion that toppled Saddam Hussein. They have been labeled "zombie" authorizations because they never expire but their original purpose no longer applies.
Supporters say the AUMFs should be repealed because Iraq is not a U.S. adversary and because they could pave the way for future destabilizing military action that has little to do with the original intent of the authorizations.
Some criticized Republican then-President Donald Trump's use of the 2002 Iraq AUMF for the 2020 killing of senior Iranian military commander Qassem Soleimani, who was in Iraq but whose targeting was not connected to the earlier war.
WHAT ABOUT THE 'WAR ON TERROR?'
Members of Congress are not - for now - targeting a third AUMF, which passed days after the Sept. 11, 2001, attacks. The measure authorized then-President George W. Bush to target al Qaeda for the assault on New York and Washington.
Because that AUMF also does not expire and was not limited by geography, it has been used by both Republicans and Democrats to justify military action around the globe.
But lawmakers said the ongoing campaign against militant violence is too important to repeal the 2001 authorization before a replacement is written.
WILL THE REPEAL PASS THIS TIME?Congress has tried and failed to repeal AUMFs repeatedly over the past 10 years.
Backers say things are different this time, partly because it has been 20 years since the last Iraq war began, and because Democratic President Joe Biden, a former senator, has said he supports the repeal and does not believe it will harm national security.
The measure has both Democratic and Republican co-sponsors in both the Senate and House. It is expected to easily pass the Democratic-led Senate after procedural votes were overwhelmingly in favor.
Its fate in the Republican-led House is less clear, given that support for AUMF repeals in the past has been much stronger among Democrats than Republicans.
Republican House Speaker Kevin McCarthy said this month there was a strong chance the House would pass a bill, but that it must go through committee review before the full chamber would vote.
That could delay repeal. Representative Michael McCaul, the Republican chairman of the House Foreign Affairs Committee, has said he does not think the AUMFs should be repealed until a new AUMF has been written to replace them.
(Reporting by Patricia Zengerle; Editing by Don Durfee and Jonathan Oatis)