PITTSBURGH — President Joe Biden unveiled what he called “a once-in-a-generation investment in America” here Wednesday, visiting a carpenters’ training facility to roll out a $2 trillion vision that he said would rebuild the country’s infrastructure, make “transformational progress” on climate change, and push the economy toward a more modern future while creating millions of jobs.

“It’s big — yes. It’s bold — yes. And we can get it done,” Biden said, standing alone before American flags and nearby metal scaffolding and wood planks.

The plan, Biden’s second major initiative as president, represents the first piece of a two-part proposal that could cost more than $3 trillion and raise taxes on businesses and the wealthiest Americans, while promising an array of public works upgrades, including on roads, bridges, public transit, and the country’s water supply.

Biden presented it as a follow-through on his promise at the start of his presidential campaign in 2019 to “rebuild the backbone” of the country. Both times, he chose as a backdrop this Pennsylvania city long known for its working-class character.

By fueling infrastructure spending, new jobs, and growing industries, Biden argued, his proposal would aid the “ordinary Americans” who “get up every day, work hard, raise their family, pay their taxes, serve the country,” and are seeking “just a little bit of breathing room.”

He also said it would address a “distorted” economy in which the country’s wealthiest people have gained while “everyone else was falling behind.”

“This is about opening opportunities for everybody else,” Biden said. “And here’s the truth: We all will do better, when we all do well. It’s time to build our economy from the bottom up and from the middle out.”

His speech was just the first step in what is likely to be an arduous process to pass a potentially legacy-defining effort. The plan immediately faced sharp criticism over its proposed tax increases, and it will have to navigate a narrowly divided Congress where most or all Republicans are likely to oppose it, some liberal Democrats may see it as insufficient, and some moderates are likely to worry about the price tag.

“Rather than offsetting this enormous spending binge responsibly, the Biden administration is pushing a massive tax increase by undoing large portions” of the GOP’s 2017 tax cuts, said Sen. Pat Toomey (R., Pa.), crediting those cuts with “the best American economy of my lifetime.” He added: “We should be trying to get back to that economy, not making American workers and businesses less competitive globally.”

Biden argued that the coronavirus pandemic had exacerbated long-festering inequality, and said that while the $1.9 trillion rescue package he signed three weeks ago addressed the country’s immediate needs, “now it’s time to rebuild.”

He spoke for about 30 minutes in a cavernous but nearly empty union training center, with top Pennsylvania Democrats — including Gov. Tom Wolf, Sen. Bob Casey, Allegheny County Executive Rich Fitzgerald, and local U.S. Reps. Mike Doyle and Conor Lamb — sitting masked in socially distanced folding chairs, occasionally applauding.

Biden’s administration argues that the proposal aims to make up for decades of neglect of the country’s infrastructure, while helping the country compete with China for economic might.

The plan would rebuild roads and bridges and invest in research and development, manufacturing, job training, and clean energy. Biden calls for paying for the plan in large part by raising the corporate tax rate to 28%, from 21%, and increasing taxes on businesses earning money overseas.

It would require 15 years of new tax revenue to pay for what the administration envisions as eight years of spending. While the second phase of Biden’s plan is likely to include tax increases on individuals, Biden said Wednesday that “no one making under $400,000 will see their federal taxes go up. Period.”

He noted that the new corporate tax rate would still be below the 35% rate in place until the Republican tax cuts four years ago.

Much of the plan focuses on traditional infrastructure — repairing the country’s 10 most economically significant bridges, along with 10,000 smaller ones; funding projects along Amtrak’s Northeast Corridor; adding $85 billion for public transit, modernizing 20,000 miles of roads, and replacing all of the country’s lead pipes. But it’s also woven with nods toward other key Biden priorities, such as fighting climate change, addressing racial inequality, and aiding rural areas that have often missed out on the country’s economic gains.

“There’s talent and innovation everywhere,” the president said, arguing his plan would extend benefits even into small towns far from the coastal centers of power.

Among the steps are a vast expansion of broadband access, particularly in rural areas; money to rebuild crumbling schools; building 500,000 electric vehicle charging stations by 2030, and building or rehabilitating energy-efficient homes. The plan would spend $400 billion on home care for senior citizens and people with disabilities, with an administration outline noting that care workers “are disproportionately women of color.”

“Imagine knowing that you’re handing your children and grandchildren a country that will lead the world in producing clean energy technology,” he said.

Biden said the plan would also dedicate $180 billion to research and development, the largest nondefense budget increase in American history. There’s money for job training meant to help workers in a changing economy transition to new, growing sectors.

» READ MORE: Why Joe Biden is pitching his infrastructure plan in Pittsburgh, where he launched and ended his campaign

The second piece of Biden’s infrastructure program, expected to be unveiled in the coming weeks, could reportedly add another $1 trillion or more in spending, along with another round of proposed tax increases.

That plan is expected to focus on education and making work more accessible, with provisions such as free community college and universal prekindergarten, subsidies for child care, and a national paid-leave program to help working parents care for children.

Taken together, the two proposals, coming close on the heels of the $1.9 trillion stimulus package approved earlier in March, would represent a massive burst of investment and government spending that could reshape the nation’s economy and, Democrats hope, address growing divides around race, education, and opportunity.

Business groups, while welcoming the calls to invest in infrastructure, blasted the tax increases as counterproductive moves that would stunt economic growth.

On the other side, some liberals said the proposal fell short of the needs and the challenges of climate change. Some House Democrats, including Bill Pascrell and Josh Gottheimer of New Jersey, warned that they won’t support the plan unless it fully restores the deduction for state and local taxes. New Jerseyans are among the biggest beneficiaries of the provision, which was limited by the 2017 changes to the tax code. .

The early back-and-forth signaled that the bill is likely to face a more difficult road to passage than Biden’s coronavirus stimulus package, even if Democrats are again able to avoid the Senate filibuster using special rules for fiscal measures. Their control of the House is narrow, and the Senate is evenly split, meaning Democrats can’t afford to lose a single vote in the chamber without coaxing some Republican support.

“It’s fitting that President Biden chose Pittsburgh to announce his ambitious, far-reaching jobs and infrastructure plan,” Tom Conway, president of the United Steelworkers International union, said in a statement. “This city and so many like it across our nation are the homes of not only the industries that will fuel this initiative but also the union members who stand ready to do the work.”

» READ MORE: Pennsylvania and N.J. are hoping for billions from Biden for roads, bridges, new transit lines

The U.S. Chamber of Commerce hailed the idea of “a big and bold” infrastructure program but argued Biden’s proposal “is dangerously misguided” in how he would pay for it. “We strongly oppose the general tax increases proposed by the administration which will slow the economic recovery and make the U.S. less competitive globally — the exact opposite of the goals of the infrastructure plan,” it said a statement.

Other business groups echoed the warning that tax hikes will cost jobs.

“Investment in infrastructure needs to be a priority, but this legislation appears to be less about improving infrastructure and a lot more about a political agenda, at the expense of sound economic policy that benefits all Americans,” said National Retail Federation president Matthew Shay.

Biden said he would invite Republicans to the Oval Office to talk about their ideas but said there can be no question about passing the plan.

Recent history, however, suggests a fierce partisan battle is likely.