Sens. Rand Paul (R–Ky.) and Tom Udall (D–N.M.) announced this morning that they'd be introducing a bill to withdraw U.S. troops from Afghanistan and repeal the legal justification that has been used for numerous other conflicts in our long-running war on terror.

"We've accomplished our mission in Afghanistan and it's time to bring our troops home," said Paul to reporters this morning. "This has been a long war. We've spent over $2 trillion total. 2,300 have lost their lives in Afghanistan, and 20,000 [have been] wounded."

"It is Congress that has failed to conduct its oversight duty of this war. We must step in and step up. We must ensure that another generation of Americans is not sent to fight a perpetual war," added Udall.

The bipartisan American Forces Going Home After Noble Service Act—or AFGHAN Service Act—would require the Secretary of Defense, within 45 days of the bill's passage, to come up with a plan to pull all U.S. military forces out of Afghanistan within a year, save for a small number of troops guarding America embassies, consulates, or supporting "intelligence operations authorized by Congress."

The bill would also repeal the 2001 Authorization for the Use of Military Force (AUMF) either within 395 days of the bill's passage, or after all U.S. troops have left the country—whichever comes first.

The 2001 AUMF was passed in the wake of the 9/11 terrorist attacks and has been pointed to as the legal justification for numerous American military interventions including not just the one in Afghanistan, but also Iraq, Syria, Somalia, the Philippines, and Niger. Repealing that legislation could hamper the White House's ability to wage a number of our current overseas interventions, says John Glaser, a foreign policy scholar at the Cato Institute.

"This could have implications for the rollback of the so-called forever war in more countries than just Afghanistan. That would be another huge benefit of this," says Glaser.

Glaser also praised the bill's tight timeline and its authors' willingness to reestablish limits on the ability of the president to fight overseas wars, telling Reason, "it's a good sign that someone is actually reasserting Congress' power over the president's war powers, and it's obviously a long time coming."

In a video statement accompanying the release of the bill, Paul noted that original purpose of defeating Al Qaeda in Afghanistan had been achieved, and that the U.S. was now engaged in an expensive, fruitless, nation-building exercise that's seen American taxpayers pay for massive boondoggles like an unusable natural gas station and an unfinished luxury hotel in downtown Kabul.

Ending our nation-building efforts in the country would save $51 billion said Paul, $7 billion of which would be paid out as one-time $2,500 "victory bonuses" to the three million U.S. military personnel that have fought in the war on terror.

When asked about President Donald Trump's position on the bill, Paul said he thought his legislation was in line with the president's non-interventionist impulses.

"I've talked to the president many times about this, and I think his instincts and his intentions are that we really have been long enough in Afghanistan and that we have completed our mission," said Paul, saying that even in private meetings with other Republican lawmakers, the president frequently pushes back on arguments for continued intervention in the country.

The trouble, says Paul, rests with some of the president's advisors who might not share his views on America's overseas wars. "He does have some people around him that are more of the 'stay forever' crowd that makes it a little hard to get his policy done," said Paul. "I don't think his views have changed on this."

The Kentucky senator was candid about the bill's slim chances in Congress, pointing to the Senate's passage of a resolution in early February condemning Trump's late 2018 statements about pulling out of Afghanistan and Syria.

The bill, argues Paul, is nevertheless an important conversation starter that will help build support for ending America's longest war. "Sometimes you have to introduce things that won't pass in the beginning, but it gives us a rallying cry," said Paul, adding that "war's a terrible thing and we should only do it when we have to."