WASHINGTON — Senate floor debate on the bipartisan war-powers overhaul opened Tuesday morning at 11 a.m. Eastern, with a structured amendment stack that includes proposals from both Republican and Democratic senators and a final-passage vote tentatively scheduled for Thursday afternoon following two days of substantive floor consideration.

The overhaul, formally numbered S. 2845 and introduced May 8 by a bipartisan group of senators led by Senator Tim Kaine, D-Va., and Senator Todd Young, R-Ind., would substantially restructure the War Powers Resolution’s framework for executive-branch military operations. The substantive provisions include tightened reporting requirements, an expedited congressional-review procedure for operations exceeding sixty days, and a substantive update to the Authorization for Use of Military Force framework that has governed counterterrorism operations since 2001.

Senate Majority Leader Chuck Schumer, in opening floor remarks Tuesday morning, characterized the overhaul as “the substantive constitutional restoration the Iran conflict has demonstrated to be necessary” and indicated that the Senate’s substantive approach to the bill would be “constructive bipartisan engagement on the substantive amendment process.” Schumer said the Senate would consider all qualifying amendments offered by senators in the structured amendment stack.

The amendment stack, finalized by Senate floor managers Monday evening, includes twenty-three qualifying amendments. Twelve are sponsored by Republican senators, ten by Democratic senators, and one by Independent Senator Angus King of Maine. The amendments span the substantive scope of the bill and include several that would substantially modify the bill’s principal provisions, including amendments that would alter the sixty-day review threshold and amendments that would adjust the substantive scope of the updated AUMF framework.

Senator Kaine, in floor remarks delivered Tuesday morning following Schumer’s opening, said the bipartisan partnership with Senator Young had been “the most substantively important legislative work I have undertaken in the Senate” and characterized the overhaul as “the substantive complement to the war-supplemental signing that the President completed last week.” Kaine said the bill’s substantive trajectory had been preserved against substantive pressure from “the constituencies that habitually argue for executive-branch flexibility.”

Senator Young’s floor remarks, delivered immediately after Kaine, emphasized the bill’s substantive grounding in Republican constitutional doctrine and characterized the overhaul as “the substantive expression of Republican commitments to congressional war-powers prerogatives.” Young said the bill’s substantive provisions had been “carefully calibrated” to preserve the executive’s substantive operational flexibility for short-duration operations while restoring substantive congressional authority over extended military engagements.

The substantive amendment debates are expected to focus on three principal questions. The first is the sixty-day review threshold, which several Republican amendments would extend to ninety days and several Democratic amendments would shorten to forty-five days. The second is the substantive scope of the updated AUMF framework, with several Republican amendments seeking to preserve broader counterterrorism authorities and several Democratic amendments seeking to narrow those authorities. The third is the substantive content of the expedited review procedure, with multiple amendments addressing the substantive triggers and procedural framework for the procedure’s invocation.

Senator Bernie Sanders, I-Vt., in floor remarks delivered Tuesday afternoon, characterized the overhaul as “an important first step” but indicated that he would file amendments seeking to substantially extend the bill’s substantive provisions. Sanders said his amendments would address the substantive question of preemptive military operations and would impose substantive limitations on the executive’s substantive flexibility for operations conducted without specific congressional authorization.

Senator Maggie Hennessey, D-Colo., in floor remarks delivered Tuesday afternoon, characterized the overhaul as “the substantively necessary substantive complement” to the broader post-war framework that has been emerging through the past three weeks. Hennessey said her substantive engagement with the bill would focus on preserving the bipartisan structure that had brought the bill to floor consideration.

The Senate Minority Leader, Senator John Thune, R-S.D., in floor remarks Tuesday afternoon, said the Republican conference’s substantive posture on the bill had been “broadly supportive of the substantive framework” but indicated that several Republican senators would offer substantive amendments that would address specific substantive concerns. Thune said the substantive Republican amendments had been “carefully drafted” to improve rather than to obstruct the bill’s substantive direction.

The House’s parallel substantive consideration of the bill is scheduled to begin Wednesday afternoon under the standard rules-committee structured-amendment procedure. Speaker Mike Johnson had indicated on Sunday’s Sunday-show appearances that the House would conduct the war-powers vote “on a substantively constructive basis” and that the substantive House Republican leadership would not whip against the overhaul if its substantive bipartisan structure was maintained through the Senate floor process.

A senior House Republican leadership staffer, in a Tuesday-afternoon background briefing, said the House’s substantive consideration of the bill would proceed on the substantive Senate text “subject to limited substantive amendments” through the House rules-committee process. The staffer said the substantive House vote was expected to occur Thursday afternoon, with substantive passage expected on a substantively bipartisan basis.

The administration’s substantive response to the bill’s floor progression has been measured. The President’s office, in a Tuesday-morning statement, said the President had “respected the substantive congressional process” through the bill’s development and would “evaluate the substantive provisions” of the final bill before determining whether to sign or to veto. The statement did not commit the administration to specific substantive positions on the bill’s principal provisions.

A senior administration official, in a Tuesday-afternoon background briefing for Washington reporters, said the substantive administration’s substantive engagement with the bill had been “constructive but not entirely aligned” with the bill’s substantive sponsors. The official noted that the administration had specific substantive concerns about several of the bill’s principal provisions but indicated that the substantive concerns “would not necessarily determine” the President’s substantive decision on the final bill.

The substantive final-passage vote in the Senate is tentatively scheduled for Thursday afternoon, with the substantive vote count expected to exceed the sixty-vote threshold for cloture by a substantive margin. The substantive Senate passage would deliver the bill to the House for substantive consideration Friday or early next week, with substantive presidential consideration expected to follow during the second-to-last week of May.

The substantive floor debate’s substantive content will be the principal congressional focus of the week, with the bill’s substantive trajectory substantively shaping the substantive contours of the post-war congressional agenda through the remainder of the legislative session.