Since arriving in the Senate in 2013, Sen. Tim Kaine (D-Va.) has pushed for the Foreign Relations Committee to forge bipartisan consensus on an authorization for the use of military force because the existing AUMF is so outdated. (Steve Helber/AP)

Sen. Tim Kaine (D-Va.) has never been closer to seeing his quixotic bid to draft a new war resolution come to fruition.

Since arriving in the Senate in 2013, Kaine has pushed for the Foreign Relations Committee to forge bipartisan consensus on an authorization for the use of military force, because the existing AUMF, as war resolutions are known in the Capitol, is so outdated.

Instead, like many other issues of foreign policy, Congress has fallen down on the job and allowed the president — first George W. Bush, then Barack Obama and now Donald Trump — to operate in the vacuum and launch military actions without much direction or restraint from Congress.

This has left the 2016 Democratic vice-presidential nominee endlessly frustrated. Earlier this year, the war resolution talks were left for dead, even as every Democrat and quite a few Republicans grew increasingly uncomfortable with President Trump’s zigzag approach to diplomacy.

By Tuesday morning, however, Kaine emerged from a meeting with Sen. Bob Corker (R-Tenn.), chairman of the Foreign Relations Committee, more optimistic than ever that at least one committee would take a responsible action on matters of war and peace.

“We’re close. There’s one item that we’re still working out, but we feel good. We’ve made some real progress,” Kaine said in a midday interview.

Most important is that Corker and Kaine are in agreement over the biggest stumbling block that has bogged down previous talks, reaching a compromise on how long the new war resolution would last.

Corker, who declined to detail the pending legislation, credited Kaine with being “the driving force on the Democratic side” of the war debate. The legislation will only serve as a replacement to the existing 2001 AUMF, which deals with terrorist groups and nonstate actors. It will not address possible missile strikes against the Syrian government for an alleged gas attack on citizens this month.

The tentative plan is to unveil the legislation Thursday and then hold a formal committee markup — debate, amendments and possibly approval — on April 19. After that, it is anyone’s guess whether Senate Majority Leader Mitch McConnell (R-Ky.) and House Speaker Paul D. Ryan (R-Wis.) will bring the war bill to the full Congress for consideration.

But in a Congress where shutting down the government only for a few hours is considered an accomplishment, just getting a bipartisan vote for a war resolution from one committee would qualify as quite a success.

“I think the trade-off of making a principled compromise, with respect to a particular facet of an AUMF, absolutely outweighs the drawbacks of doing nothing,” said Sen. Todd C. Young (R-Ind.), a former intelligence officer in the Marine Corps.

Just in his second year in the Senate, Young, 45, emerged as an honest broker to help push negotiations along. For perspective, when the existing war resolution was approved just after the September 2001 terrorist attacks, Young was 29 and about to start working for then-Sen. Richard G. Lugar (R-Ind.), a foreign-policy luminary.

That AUMF was intended to deal with al-Qaeda and its leader, Osama bin Laden, who was killed by U.S. Special Forces in a raid in Pakistan seven years ago. Instead, the mission grew and grew, under Republican and Democratic administrations, with recent years focused on fighting the Islamic State in Syria and Iraq, and affiliates throughout northern Africa.

Fewer than a quarter of the House was in office for the 2001 war debate, and a majority of today’s senators were not in Congress at that time.

“I think we owe it to our troops to cast a vote now that we have so many new members of Congress,” said Young, who took a seat in the House in 2011.

Some details need to be worked out, but Corker and Kaine both declared themselves contented with how they resolved the timeline of the war resolution. Democrats have demanded time limits to authorization, a “sunset” that would force Congress to have to act again after a certain number of years to keep the war posture going. Some liberals have also pushed for limitations about the geography of the battlefield.

“I’m willing to have less tactical and geographic limitations as long as there is a sunset. But if there isn’t a sunset, then the tactical, geographic limitations have to be tighter,” said Sen. Chris Murphy (D-Conn.).

Republicans have always objected, preferring to rely on the recommendations of the generals.

The compromise, as described by several officials involved in the talks, was to approve the AUMF beyond this presidential term, likely four years, and then ask the administration to submit a new war proposal. If no new proposal were presented, the existing war resolution would still be law, but there would then be a congressional review period and, most likely, then a vote on the existing war resolution.

It is likely run into some conservative and liberal opposition, because conservatives will argue that it is placing some limits on military officials, and liberals will not like the lack of a hard-and-fast sunset.

Kaine said it was much better than the alternative, which would be more lingering inaction by Congress.

“Compared to what we have now — which is essentially a blank check — what we are doing puts what, I think, are reasonable limitations on when, where and, most importantly, who it is that we’re fighting against,” he said.

Each side will cite different nuances in the bipartisan bill. Republicans are already declaring that there are no geographic limits coming in the bill, and they believe the timeline is not a sunset.

But both sides are happy to finally have Congress — even if it’s just one committee — taking up the issue.

“There’s just our constitutional prerogative as the legislative branch of government,” Young said, arguing it was time to “assert ourselves.”

“We haven’t been doing that in recent years,” he said.

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