WASHINGTON — The House overwhelmingly passed a $741 billion defense policy bill on Tuesday that would require that Confederate names be stripped from American military bases, defying President Trump’s veto threat and moving lawmakers one step closer to a potential showdown in his final weeks in office.
The 335-78 bipartisan vote to approve the legislation that authorizes pay raises for American troops reflected optimism among lawmakers in both parties that Congress would be able to force the enactment of the bill over Mr. Trump’s objections, in what would be the first veto override of his presidency. The margin surpassed the two-thirds majority both the House and Senate would need to muster to do so.
It also amounted to a remarkable break from the president by Republicans, who refused to defer to Mr. Trump’s desire to derail the critical bill as his time in the White House comes to a close.
“Today the House sent a strong, bipartisan message to the American people: Our service members and our national security are more important than politics,” said Representative Adam Smith, Democrat of Washington and the chairman of the Armed Services Committee.
Congress has succeeded in passing the military bill each year for 60 years, with lawmakers in both parties relishing the opportunity to project strength on national security issues and support for the military. But Mr. Trump’s objections have threatened to upend that tradition, as he has warned since the summer that he would veto the bill.
He did so at first over the mandate — broadly supported by lawmakers in both parties in both chambers, as well as at the Pentagon — that the Defense Department strip the names of Confederate figures from military bases. More recently, Mr. Trump has shifted the focus of his threat, demanding that the bill include an unrelated repeal of a legal shield for social media companies.
“I hope House Republicans will vote against the very weak National Defense Authorization Act (NDAA), which I will VETO,” Mr. Trump wrote on Twitter on Tuesday in the hours before the vote. “Must include a termination of Section 230 (for National Security purposes), preserve our National Monuments, & allow for 5G & troop reductions in foreign lands!”
All but 40 Republicans — many of whom oppose the defense bill each year as a matter of principle — disregarded that appeal. Mr. Trump’s late demand to include the sweeping rollback of legal protections for social media companies in the military bill has divided his party. Some Republican leaders have publicly described the move as untenable and privately called it unreasonable.
Senator James M. Inhofe of Oklahoma, the chairman of the Armed Services Committee, has said he will try to override a veto and has been privately lobbying the president to support the bill. But while Representative Kevin McCarthy, Republican of California and the minority leader, said on Tuesday that he would support the measure, he told reporters he would not vote to override an eventual veto, suggesting that members of the president’s own party should not join such an effort.
“Section 230 needs to get done,” Mr. McCarthy said, referring to the repeal of the legal liability for social media companies.
Senior lawmakers shepherding the legislation have hoped that mustering a veto-proof majority in favor of it would cow Mr. Trump into signing the bill. But they privately conceded that the president’s mercurial nature made it difficult to predict what he might do.
The sheer willingness of Republican leaders to mow over Mr. Trump’s objections — after initially laboring for weeks to try to accommodate them — was a stark departure from the deference the president has normally received on Capitol Hill from his own party. It underscored lawmakers’ impatience with Mr. Trump’s attempt to derail the national security measure over a social media provision that has nothing to do with it.
“As important as this issue is, it falls outside the jurisdiction of this bill, and deserves its own domain, and a separate vote,” said Representative Don Bacon, Republican of Nebraska and a member of the Armed Services Committee. “Do you think you’ll get a better bill in two months? The answer is no.”
The legislation contains a number of noncontroversial, bipartisan measures, including new benefits for tens of thousands of Vietnam-era veterans who were exposed to Agent Orange, a 3 percent increase in pay for service members and a boost in hazardous duty incentive pay.
But it also includes a slew of measures pushed by Democrats that were expressly intended to constrain some of the impulses that Mr. Trump displayed during his time in office.
The bill would take steps to slow or block Mr. Trump’s planned drawdown of American troops from Germany and Afghanistan, and would make it more difficult for the president to deploy military personnel to the southern border. Lawmakers also included language that would compel the president to impose new sanctions against Turkey for its purchase of a Russian antiaircraft missile system, a step Mr. Trump has been reluctant to take despite the urging of lawmakers in both parties.
The legislation also directly addresses the protests for racial justice spurred over the summer by the killing of Black Americans, including George Floyd, at the hands of the police. It would require all federal officers enforcing crowd control at protests and demonstrations to identify themselves and their agencies. And it contains the bipartisan measure that directs the Pentagon to begin the process of renaming military bases named after Confederate leaders, a provision that Democrats fought to keep in the bill.
“We cannot ask today’s young servicewomen and men to defend our nation, while housing and training them and their families on bases honoring those who betrayed our country in order to enslave others,” said Representative Anthony G. Brown, Democrat of Maryland, and one of the sponsors of the provision. “America’s proudest achievements are defined by men and women who expanded the promise of freedom. That’s the history and those are the people we should honor.”
The legislation is slated to be considered this week in the Senate, where it is expected to pass overwhelmingly before it is sent to the president’s desk.
If Mr. Trump were to follow through with his threatened veto, the House would be the first to try at an override.