PHILADELPHIA — President Joe Biden returned to Pennsylvania Friday to use the critical battleground state again as a backdrop for some of his favorite political themes, championing steep increases in public works spending and detailing how bolstering green energy can spur U.S. manufacturing.

But the world has changed since Biden visited a familiar place to talk up familiar topics.

The war between Israel and Hamas has scrambled geopolitics and potentially reshuffled a 2024 presidential race beginning to heat up. Getting the public’s attention could be a tall order given the focus on fighting and atrocities in Gaza, and the Americans among those killed by Hamas.

The president started his speech Friday talking about the conflict, telling the crowd that he had spoken by video conference for an hour or so with the families of 14 Americans missing in the attacks.

“The more we learned about the attack the more horrifying it becomes,” Biden said.

Other domestic matters also are competing for political attention, with the fight over choosing the next Republican House speaker potentially imperiling continued U.S. aid to Ukraine, and a United Auto Workers strike entering its fifth week. On top of all that, the president’s son, Hunter, is facing federal gun charges and Biden himself recently sat for interviews with a special prosecutor investigating his handling of classified documents — though that may signal the case is nearing a conclusion.

But Biden still made his case at the marine terminal in Philadelphia, where he declared it was one of seven regional hubs selected around the country to produce and deliver hydrogen fuel that can run factories and other facilities, as well as key components of heavy industry, to limit greenhouse gas emissions. A centerpiece of the Biden administration’s clean energy plan, the hubs will be paid for using $7 billion from the sweeping infrastructure package that cleared Congress in 2021.

“These hubs are about people coming together across state lines, across industries, across political parties to build a stronger, more sustainable economy and to rebuild our communities,” he said.

Any struggle to shift attention to Biden’s domestic agenda highlights larger questions about the president’s overall reelection strategy and whether messaging primarily built around the president’s policy accomplishments and ability to govern can compete with ever-changing world events that shake up politics in real time.

“Will the country care? In the political class, in the news-absorbing part of the population, nationally? No,” Cathal Nolan, director of the International History Institute at Boston University and the author of several books on diplomatic and military history, said of Biden’s hydrogen production announcement.

“But I don’t think that’s what infrastructure speeches are about, ever,” Nolan added. “I think it’s about the local impact.”

Indeed, allies contend Biden should stay on political message as he seeks reelection, stressing steady leadership approaches even in a time of crisis, and highlighting how the government is improving middle-class lives as he heads into a potential rematch with Donald Trump, who has a commanding lead in the 2024 Republican presidential primary.

The Philadelphia speech was part of what his administration is calling the third installment of Biden’s Investing in America Tour, which will see the president, Vice President Kamala Harris and key Cabinet members travel the country to promote economic policies. Biden heads to Colorado on Monday.

“When there’s an international crisis, you’ve got to be leading,” said Joel Rubin, who was an Obama administration State Department official and a veteran of Bernie Sanders’ 2020 presidential campaign. “The fact that he’s going to continue to be out there demonstrates leadership.”

Friday’s trip notwithstanding, Biden has made the situation in Gaza a priority, speaking frequently with his foreign advisers and with Israeli Prime Minister Benjamin Netanyahu. He met with Jewish community leaders at the White House this week and has said that “the U.S. has Israel’s back” while decrying the “sheer evil” of Islamic militants.

“We’re making sure Israel has what it needs to defend itself and respond to these attacks, he said. ”It’s also a priority for me to address the humanitarian crisis in Gaza.”

The president also announced other policy efforts this week, including announcing more attempts to curb “ junk fees,” and meeting with CEOs.

Rubin said the Biden administration has championed a “foreign policy for the middle class,” which emphasizes domestic economic and industrial strength and reinvigorating global alliances. That helps explain the thought process behind Friday’s speech, he said.

“Communicating why his policy is working for the American people economically … that undergirds American national power overseas. You take that away, you have nothing,” said Rubin, who also founded J Street, a liberal Jewish advocacy group in Washington, and is running for Congress in Maryland.

Biden on Friday insisted the clean energy investment was an investment in the future — one of several initiated by his administration.

“I truly believe this country is about to take off, for the first time in a long time we’re actually investing in America,” he said.

Still, selling Biden’s economic agenda to voters wasn’t easy even before the outbreak of war in Gaza. Just 36% of U.S. adults approved of Biden’s handling of the economy in August, slightly lower than the 42% who approved of his overall performance, according to a poll from The Associated Press-NORC Center for Public Affairs Research.

Whatever the message, the president can help himself politically by staying focused on Pennsylvania, said longtime Democratic strategist Robert Shrum.

“If he wins the state he’s very likely to win reelection,” Shrum said. “So they can do the event in Philadelphia and get a lot of attention for it.”

Biden appears to be betting on that strategy, heaping Pennsylvania with attention that has included a visit per month recently — acutely aware that it is one of a few toss-up states where outcomes can really sway the election, along with Georgia and Arizona, as well as perhaps Wisconsin and Michigan.

Since formally announcing his reelection bid in April, Biden addressed some of the nation’s largest unions at the Philadelphia convention center after they jointly endorsed him in June, the only 2024 campaign rally he’s held so far. He returned to Philadelphia in July, visiting a shipyard where he talked up how organized labor would lead a major push toward embracing green energy.

He made an August trip for a funeral to Scranton, Pennsylvania, where he was born, and was in Philadelphia last month for an ALF-CIO Labor Day event.

“It’s the power of incumbency that he can work policy speeches into places that he’s going to,” said Mustafa Rashed, a Philadelphia-based Democratic strategist. “Everything is about 2024 at this point.”