President Biden on Wednesday officially threw in the towel on his roughly $1.8 trillion social welfare and climate bill, saying he would instead break up the legislation and try to pass “big chunks.”

The pivot to a piecemeal approach on the massive bill, which was the centerpiece of the president’s economic agenda, confirmed the reality most in Washington had already accepted: The big bill is dead.

“It’s clear to me that we’re probably going to have to break it up,” Mr. Biden said at a rare White House press conference marking his first year in office. “I think we can break the package up, get as much as we can now and come back and fight for” other elements after the midterm elections in the fall.

The president said he hopes to still push forward this year with a portion of the bill totaling roughly $500 billion for climate change and energy policies, as well as another piece for spending on early childhood education.

He suggested that he will ditch, for now, a revival of an expanded child tax credit that expired this month and massive aid for community college tuition. Abandoning those priorities likely will anger the party’s liberal base in a pivotal election year.

The biggest obstacle in the president’s party to the larger package, Sen. Joe Manchin III of West Virginia, said after the press conference that he had not renewed discussions with the White House or Senate leaders about a piecemeal approach.

“Not yet. No one has come to me on that,” he said.

On the same night that the Senate was poised to deal the president a high-profile defeat on legislation to overhaul elections, Mr. Biden further conceded that he might seek to break his voting law proposals into “chunks” as well.

Asked whether the midterm elections would be fair and legitimate without the sweeping partisan legislation, Mr. Biden stunned some viewers by responding, “It depends on whether or not we’ll be able to make the case to the American people that some of this is being set up to try to alter the outcome of the election.”

The president also raised eyebrows in Washington and in Ukraine by appearing to give Russian President Vladimir Putin the green light for a military incursion of its neighbor to the west, as long as it is “minor.”

“It’s one thing if it’s a minor incursion … but if they actually do what they’re capable of doing … it is going to be a disaster for Russia if they invade Ukraine,” Mr. Biden said.

The White House issued a clarification within an hour after the president left his podium.

“President Biden has been clear with the Russian President: If any Russian military forces move across the Ukrainian border, that’s a renewed invasion, and it will be met with a swift, severe and united response from the United States and our allies,” White House press secretary Jen Psaki said.

Sen. Ben Sasse, Nebraska Republican, called the president’s press conference “an absolute train wreck that will have serious consequences.”

“President Biden basically gave Putin a green light to invade Ukraine by yammering about the supposed insignificance of a ‘minor incursion,’” Mr. Sasse said. “He projected weakness, not strength. If that wasn’t bad enough, he undermined trust in our elections here at home. This isn’t hard: if you’re the president of the United States, you affirm public trust in our elections. President Biden ran on a return to normalcy, but what we saw today ain’t it.”

In a nearly two-hour press conference, the president acknowledged that his administration still needs to get inflation and COVID-19 under control, but he insisted he has made “enormous progress.” He vowed to “stay on this track” and rejected the suggestion that his campaign promises were too rosy.

“I didn’t overpromise,” Mr. Biden said. “But I have, probably, outperformed what anybody thought would happen.”

His “Build Back Better” bill derailed in the Senate in December when Mr. Manchin announced his opposition. The measure needed the support of all 50 Senate Democrats to pass in a party-line vote.

All Senate Republicans oppose the huge spending bill. Many say the administration’s big-spending priorities were contributing to inflation, which reached a 40-year high last month.

The president put most of the onus on the Federal Reserve to bring rising prices under control.

Oddly, Mr. Biden led off the press conference by saying one way to control inflation was for Congress to pass “Build Back Better,” which he conceded less than an hour later was essentially dead as a package deal.

“If price increases are what you’re worried about, the best answer is my Build Back Better plan,” he told viewers.

Mr. Biden repeatedly expressed exasperation with Republicans, saying he “underestimated” their fervor for opposing his agenda in his first year.

“They weren’t nearly as obstructionist [during the Obama administration] as they are now,” Mr. Biden said. “I don’t know what their agenda is now. What would be the Republican platform right now? I honest to God don’t know what they’re for.”

He complained that former President Donald Trump still has an iron grip on the Republican Party a year after leaving office in a bitterly contested election that Mr. Trump claims was rigged.

“Did you ever think that one man out of office could intimidate an entire party where they’re unwilling to take any vote contrary to what he thinks should be taken for fear of being defeated in a primary?” Mr. Biden said.

At times, he sounded like former President Barack Obama, who expressed hope in 2012 that Republicans’ “fever” against him would break when he won reelection.

“We’ve got to break that. It’s got to change,” Mr. Biden said of the GOP’s opposition that he termed “stalwart.”

The president said five Republican senators talk to him behind the scenes and express support for his policies, but they won’t support him publicly. He would not name them.

“My buddy John McCain is gone,” the president said of the late GOP senator from Arizona.

Last August, 19 Republican senators voted for the administration’s $1.2 trillion infrastructure plan, which Mr. Biden touts as the biggest success of his presidency so far.

Mr. Biden’s job-approval rating has reached its lowest point, about 42% in an average of major polls, and two-thirds of Americans say the nation is on the wrong track.

While the president vowed to keep to his agenda, he also said he intends to make three big changes in his second year. He wants to get out of the White House more often, seek more advice from “experts” outside his administration and become “deeply involved” in campaigning for Democrats in the midterms.  

“I have not been out in the community nearly enough,” Mr. Biden said. “I’ve been here [at the White House] an awful lot. I don’t get the chance to look people in the eye, because of COVID, and things that are happening in Washington — to be able to go out and do the things that I’ve always been able to do pretty well, connect with people. I think that’s a problem that is my own making, by not communicating as much as I should have.”

Asked why he has tried to move the country to the left, Mr. Biden rejected the accusation.

“I’m not,” he insisted. “I’m not Bernie Sanders. I’m not a socialist. I’m a mainstream Democrat.”

He referred to his first year as one “a year of challenges but also a year of enormous progress,” citing 6.4 million jobs created and unemployment falling to 3.9%. Mr. Biden said the administration will redouble its efforts to control the COVID-19 pandemic and inflation.

“The best days of this country are still ahead of us,” he said.

S.A. Miller contributed to this report.

Altimeters are a key part of the 787’s landing system, turning on the reverse thrusters that slow the plane once it has landed. Mr. Lemme said a Boeing patent suggested that the function was totally automated, meaning that even a pilot landing a 787 manually would not be able to reverse the plane’s thrusters if the altimeter malfunctioned. The 787’s landing gear brakes, which are triggered by weight, would still function, as would its wing spoilers, which are only partly controlled by altimeter readings. But Mr. Lemme said a lack of reverse thrusters would make it difficult for pilots to stop planes before they reached the end of the runway.

“You absolutely could have some planes running through runways,” he said.

Boeing did not respond to a request for comment.

The F.A.A. on Friday issued a notification that it had detected “anomalies” that “regardless of weather or approach” could cause 5G interference to affect a number of the 787’s automated systems. “The presence of 5G C-band interference can result in degraded deceleration performance, increased landing distance and runway excursion,” the agency said. The notification covers 137 787s in the United States and more than 1,010 worldwide.

Why weren’t these concerns addressed earlier?

AT&T and Verizon’s decision to temporarily limit their new 5G network within two miles of airports should address many of these safety concerns — at least for now. But the start of 5G has been years in the making, raising questions about why airlines, the F.A.A., the wireless companies and the F.C.C. did not resolve them earlier.

Ms. Furchtgott-Roth said previous warnings from aviation experts had been ignored. She said that in December 2020, the Transportation Department sent a letter to the National Telecommunications and Information Administration warning that allowing 5G to operate in its proposed frequency band would cause problems for flight safety systems. She said that letter was never passed along to the F.C.C. and to wireless companies.

Instead, the F.C.C., relying on its own research that cleared 5G of safety concerns, went ahead with a planned auction. In February, carriers bid more than $80 billion to use that portion of the wireless spectrum for 5G.

“Wireless carriers have a right to expect a return on their investment,” Ms. Furchtgott-Roth said. “But you should be very happy that the F.A.A. is taking a strong stance to ensure people’s safety.”

Google and Apple are furious with antitrust legislation getting a fresh look in Congress and warned that what’s bad for them is bad for America.

As the Senate Judiciary Committee prepares to review new antitrust proposals, the Big Tech titans are working to undermine support for the bills that could damage their market power.

The judiciary committee is reviewing two proposals on Thursday: the Open App Markets Act, which intends to foster competition with Apple and Google’s app stores, and the American Innovation and Choice Online Act, which seeks to block Big Tech companies from giving preference to their products and disadvantaging competitors.

Kent Walker, Google’s global affairs and chief legal officer, said legislation debated by Congress will “break” its search, maps and email services and give foreign companies an edge. Mr. Walker did not name the specific bills his company opposes in his scathing post on the company’s blog.

“We’re deeply concerned about these unintended consequences,” Mr. Walker wrote. “Antitrust law is about ensuring that companies are competing hard to build their best products for consumers. But the vague and sweeping provisions of these bills would break popular products that help consumers and small businesses, only to benefit a handful of companies who brought their pleas to Washington.”

Apple wrote to lawmakers in opposition to the bills and argued that the legislation would make it more difficult for Apple to protect the privacy and security of Americans’ devices, according to Bloomberg. 

Similarly, Mr. Walker wrote that antitrust legislation could prevent Google from securing its products and enable foreign competitors to innovate while Google works to meet the new American rules. 

“These bills would impose one set of rules on American companies while giving a pass to foreign companies,” Mr. Walker wrote. 

Big Tech’s defenders in the advocacy realm are targeting senators, too. The watchdog group Taxpayers Protection Alliance, which is aligned on antitrust policy with Google, said Wednesday that it was spending close to $2 million on ads opposing the legislation, and the ads are focused on 17 senators.

“China wants to beat America. The anti-tech agenda in Washington will kneecap our economy, weaken our national security, and help China win,” said a narrator in one 15-second ad. “Tell Congress to oppose these dangerous laws. Tell them to fight for American technology and America’s security.”

The Taxpayers Protection Alliance is identified by Google on its September 2021 list of groups that “receive the most substantial contributions from Google’s U.S. Public Policy and Government Affairs team.”

Also on Google’s list is the Connected Commerce Council, which said Wednesday that it is opposed to the legislation. The council said nearly 7,000 small businesses sent more than 20,000 letters to lawmakers opposing the legislation that the council thinks would force its partners, Google and Amazon, to change their operations in a way that harms small businesses. 

Google’s competitors are also writing to Congress but in support of the legislation. DuckDuckGo and You.com, which are rivals to Google’s search product, were among the companies signing on to a letter sent to the Senate Judiciary Committee urging passage of the law. 

“Dominant technologies companies’ ability to give their own products and services preferential placement, access and data on online platforms and operating systems prevents companies like us from competing on the merits,” the companies wrote. “For example, due to their gatekeeper status, dominant technology companies can: use manipulative design tactics to steer individuals away from rival services; restrict the ability of competitors to interoperate on the platform; use non-public data to benefit the companies’ own services or products; make it impossible or complicated for users to change their default settings or services or uninstall apps.”

The companies said that such tactics harm not only themselves as competitors but consumers as well.