If the president wins re-election, his climate team is likely to try to cut greenhouse gases from steel, cement and other hard-to-clean-up manufacturing.If President Biden wins a second term, his climate policies would take aim at steel and cement plants, factories and oil refineries — heavily polluting industries that have never before had to rein in their heat-trapping greenhouse gases.New controls on industrial facilities, which his advisers have begun to map out and described in recent interviews, could combine with actions taken on power plants and vehicles during his first term to help meet the president’s goal of eliminating fossil fuel pollution by 2050, analysts said. Industrialized nations must hit that target if the world has any hope to avoid the most catastrophic impacts from climate change, according to scientists.“If people look at what this administration has done on climate and say ‘This is enough,’ this country is not going to get to our goals,” said John Larsen, a partner at Rhodium Group, a nonpartisan energy research firm whose analyses are regularly consulted by the White House.But talking about more regulations at the start of what promises to be a bruising election cycle is perilous, strategists said. In particular, the prospect of new mandates from Washington regarding steel and cement, the bedrock materials of American construction, could sour the swing-state union workers courted by Mr. Biden.“If you are seen as imposing debilitating regulations on heavy industry that employs large numbers of people, you’re not only going to get a backlash from manufacturing, but labor as well,” said David Axelrod, the Democratic strategist who ran former President Barack Obama’s campaigns. “How to do that without looking like you are stabbing these industries in the back, or in the front for that matter, is a real political challenge.”Still, the urgency of global warming requires action, Mr. Larsen said. “Most other problems in America aren’t going to be 10 times worse in 10 years if we don’t do something right now,” he said. “Climate’s not like that. If this year has shown us anything, with the extreme weather and fires, it’s that it won’t just stay at this level — it’s going to break all the records we’ve just broken.”President Biden during a visit to Lahaina on Maui, which was devastated by wildfires, last month.Haiyun Jiang for The New York TimesRepublicans are eager to seize on the suggestion of additional regulations at a time when many Americans think the economy is in a downturn.“Apparently skyrocketing gas and energy prices weren’t enough for Biden, he wants to raise the prices on building and infrastructure costs and put hard working Americans further into debt,” said Emma Vaughn, a spokeswoman for the Republican National Committee. “Biden will not be elected to a second term — American families can’t afford it.”But Collin O’Mara, chief executive of the National Wildlife Federation, and others believe that after Americans have sweltered through a summer of the hottest temperatures in recorded history, watched the nation’s deadliest wildfire in over a century decimate a Hawaiian island, inhaled wildfire smoke from Detroit to Atlanta, and experienced hot-tub ocean temperatures off the Florida coast, at least some voters will be ready to embrace more climate action.Solar panel installation at a home in Norman, Okla.Mason Trinca for The New York TimesA second-term Biden climate agenda would come after the president has already delivered transformative policies to reduce greenhouse gases generated by the United States, the country that has pumped the most carbon dioxide into the atmosphere since the Industrial Revolution.Last year, Mr. Biden signed into law the Inflation Reduction Act, a landmark climate law, which will provide at least $370 billion over the next decade for incentives to ramp up sales of electric vehicles and expand wind, solar and other renewable energy. Under Mr. Biden, the Environmental Protection Agency has proposed regulations, expected to be finalized next year, designed to compel the phaseout of gasoline-powered cars and coal-fired power plants.Together, those policies could help cut the nation’s emissions nearly in half over the next decade, analysts say.And yet, it’s not enough.The United States and nearly 200 other countries agreed in 2015 to try to limit the rise in average global temperatures to 1.5 degrees Celsius (2.7 degrees Fahrenheit) by 2100, compared with preindustrial levels. Beyond that point, scientists say, the effects of deadly heat waves, flooding, drought, crop failures and species extinction would become significantly harder for humanity to handle. But the planet has already warmed by an average of about 1.2 degrees Celsius and the United States and other nations are far from meeting their goals.As emissions in the United States decline from energy and transportation, the country’s two biggest sources of greenhouse gases, industry would become the most polluting sector of the economy. That makes businesses like steel and cement manufacturing — among the most difficult to clean up — the obvious target for the next round of climate regulation.At the White House, Mr. Biden’s climate team has already envisioned a multi-step plan to cut industrial pollution if he wins re-election.The first step would use carrots, steering incentives from the 2022 Inflation Reduction Act toward nascent technologies to help factories to reduce their carbon footprint.For example, green hydrogen, a fuel produced by using wind and solar power, is muscular enough to run a steel mill but emits only water vapor as a byproduct. And cement production involves heating limestone and releasing large amounts of carbon dioxide, but several companies have been developing cement that does not emit carbon and may even absorb it.Damage to Horseshoe Beach, Fla., after Hurricane Idalia last month.Paul Ratje for The New York TimesThe second step would be to try to compel global competitors to clean up their operations through a “carbon tariff” — a fee added to imported goods like steel, cement and aluminum based on their carbon emissions.Congress would need to approve such a tax, which has support from Democrats and some Republicans. The European Union imposed a similar carbon border tax earlier this year.To justify a carbon tariff to the World Trade Organization, the United States would likely have to impose the same type of taxes on industrial pollution at home. While efforts to impose a carbon tax have long been seen as dead on arrival in Congress, the administration could instead use its executive authority to impose new top-down regulations on industrial pollution by using the 1970 Clean Air Act, which formed the basis for its proposed regulations on cars and power plants.But those policies are already under fire.Candidates seeking the Republican presidential nomination have argued that Mr. Biden’s promotion of electric vehicles and solar energy makes the United States more reliant on its chief economic rival, China, for necessary components and that cutting emissions at home does not matter when other countries continue to pollute.“If you want to go and really change the environment, then we need to start telling China and India that they have to lower their emissions,” said former South Carolina Gov. Nikki Haley at the first Republican debate last month.Mr. O’ Mara, an informal adviser to the Biden re-election campaign, said that the United States needs to push other nations to act before Mr. Biden can build support for new domestic climate measures.“If we don’t hold polluters in India and China accountable first, the politics are almost impossible,” Mr. O’Mara said.Perhaps even worse for Mr. Biden, unionized autoworkers are uneasy about his regulations designed to pivot the American market away from gasoline-powered cars and toward electric vehicles. Concerned that electric vehicles require fewer workers and a transition could cost jobs, the United Auto Workers has so far declined to endorse Mr. Biden. The union went on strike Thursday against the nation’s largest carmakers, in part over demands that workers at electric vehicle battery factories be covered by the U.A.W. contract.That discontent could spread to workers in the steel and cement industries if new regulations mean fewer jobs.Sean O’Neill the senior vice president of government affairs at the Portland Cement Association, which represents the majority of the nation’s 20 cement manufacturers, said his industry would welcome federal help to decarbonize and would consider supporting some form of a carbon tariff, under certain circumstances. But it would oppose regulations that could limit the availability of materials to build and repair buildings and bridges, he said.“Any policy that could hamper the domestic production of cement could be problematic to the downstream industries — concrete, construction,” he said.At the Biden campaign headquarters in Wilmington, the messaging strategy steers away from regulations and instead highlights the impacts of extreme weather and climate denial on the part of Republicans.Mr. Biden leaned into those themes at a Sept. 10 news conference, saying, “The only existential threat humanity faces even more frightening nuclear war is global warming going above 1.5 degrees in the next 20 — 10 years. That’d be real trouble. There’s no way back from that.”Recent surveys show that Americans are concerned about climate change and think the government and large corporations should do more to fight it, but opinion is mixed when it comes to specific policies.Representative Maxwell Frost of Florida. “Climate is paramount across the South, especially here in Florida where we are on the front lines of the climate crisis,” he said.Kenny Holston/The New York TimesIn surveys by the Pew Research Center this year, 66 percent of adults said the government should encourage wind and solar energy while just 31 percent want the country to phase out fossil fuels. Respondents were divided on the question of whether the government should encourage the use of electric vehicles, with 43 percent saying it should, 14 percent saying it should not and 43 percent saying it should neither encourage or discourage.While 54 percent of adults polled by Pew said climate change was a major threat to the country’s well-being, respondents ranked it 17th out of 21 national issues in a January survey. “Even for Democrats, who say it’s important, it’s not the top issue,” said Alec Tyson, a researcher who helped conduct the survey.The Biden campaign is betting that the real-time damage from weather disasters made worse by climate change will turn out one demographic the president especially needs — young voters in high numbers.“Climate is one of the biggest issues for us — and as we get older it will continue to be,” said Representative Maxwell Frost, 26, Democrat of Florida, who serves on the Biden campaign’s advisory board and is the only member of Congress from Generation Z.“Climate is paramount across the South, especially here in Florida where we are on the front lines of the climate crisis, with hot-tub temperatures in the surrounding ocean,” said Mr. Frost, speaking by telephone from his Orlando district soon after it was flooded by Hurricane Idalia. “The ocean water, the record heat post-hurricane, the record temperatures in the water — these are things we know and feel.” More