WASHINGTON (AP) — In a celebratory setting featuring Fourth of July picnickers, President Donald Trump enacted a set of tax cuts and spending reductions on Friday. His efforts to secure almost complete Republican backing in Congress for this crucial domestic issue could play a defining role in his pursuit of a second term.

Surrounded by Republican lawmakers and Cabinet members, Trump signed the substantial legislation on a desk stationed on the White House driveway. He then emphatically used a gavel, a gift from House Speaker Mike Johnson, which was part of the final approval process for the bill on Thursday.

Trump’s aim of marking a landmark — and controversial — legislative success by the nation’s celebration of independence was realized against odds that initially appeared daunting. This deadline was self-imposed, urging Congress to deliver the bill to him by this date. The White House’s annual Fourth of July picnic coincided with a spectacle of fighter jets and stealth bombers soaring overhead.

“America’s winning, winning, winning like never before,” Trump said, noting last month’s bombing campaign against Iran’s nuclear program, which he said the flyover was meant to honor. “Promises made, promises kept, and we’ve kept them.”

The White House was hung with red, white and blue bunting for the Independence Day festivities. The U.S. Marine Band played patriotic marches — and, in a typical Trumpian touch, tunes by 1980s pop icons Chaka Khan and Huey Lewis. There were three separate flyovers.

Trump spoke for a relatively brief 22 minutes before signing the bill, but was clearly energized as the legislation’s passage topped a recent winning streak for his administration. That included the Iran campaign and a series of U.S. Supreme Court rulingshe’s fought for.

After dark, chants of “USA, USA” rose from the picnic crowd on the South Lawn when Trump and the first lady, Melania, appeared on the Truman Balcony to watch the fireworks. They danced to “Y.M.C.A.” and waved goodbye to the crowd before they left for their home in New Jersey.

The budget legislation is the president’s highest-profile win yet. It includes key campaign pledges like no tax on tips or Social Security income. Trump, who spent an unusual amount of time thanking individual Republican lawmakers who shepherded the measure through Congress, contended “our country is going to be a rocket ship, economically,” because of the legislation.

Big cuts to Medicaid and food stamps

Critics assailed the package as a giveaway to the rich that will rob millions more lower-income people of their health insurance, food assistance and financial stability.

“Today, Donald Trump signed into law the worst job-killing bill in American history. It will rip health care from 17 million workers to pay for massive tax giveaways to the wealthy and big corporations, amounting to the country’s largest money grab from the working class to the ultra-rich,” AFL-CIO President Liz Shuler said in a statement. “Every member of Congress who voted for this devastating bill picked the pockets of working people to hand billionaires a $5 trillion gift.”

The legislation extends Trump’s 2017 multitrillion-dollar tax cuts and cuts Medicaid and food stamps by $1.2 trillion. It provides for a massive increase in immigration enforcement. Congress’ nonpartisan scorekeeper projects that nearly 12 million more people will lose health insurance under the law.

The legislation passed the House on a largely party-line vote Thursday, culminating a monthslong push by the GOP to cram most of its legislative priorities into a single budget bill that could be enacted without Senate Democrats being able to block it indefinitely by filibustering.

It passed by a single vote in the Senate, where North Carolina Republican Thom Tillis announced he would not run for reelection after incurring Trump’s wrath in opposing it. Vance had to cast the tie-breaking vote.

In the House, where two Republicans voted against it, one, conservative maverick Tom Massie of Kentucky, has also become a target of Trump’s well-funded political operation. No Democrats voted for the bill.

The legislation amounts to a repudiation of the agendas of the past two Democratic presidents, Barack Obama and Joe Biden, in rolling back Obama’s Medicaid expansion under his signature health law and Biden’s tax credits for renewable energy.

The Congressional Budget Office estimates the package will add $3.3 trillion to the deficit over the decade and 11.8 million more people will go without health coverage.

Democrats vow to make bill a midterm issue

Democratic National Committee Chair Ken Martin on Friday called the bill “devastating” and said in a statement that Trump’s signature on the legislation “sealed the fate of the Republican Party, cementing them as the party for billionaires and special interests — not working families.”

He predicted Republicans would lose their majority in Congress over it. “This was a full betrayal of the American people,” Martin said.

Trump complained Friday about Democrats opposing the bill, “and we knew that because their hatred of either the country or me or both is so great they didn’t vote at all and it’s terrible.”

He said their “standard line” is to say Republican legislation is “dangerous” or “everybody’s going to die” and “we can’t let them get away with it.” With his bill, Trump said, “it’s actually just the opposite, everybody’s going to live.”

“And I just want you to know, if you see anything negative put out by Democrats, it’s all a con job,” Trump said, defending a package that now is law.

Speaking in Iowa on Thursday night, Trump said Democrats “hate Trump — but I hate them, too.”

The package is certain to be a flashpoint in next year’s midterm elections, and Democrats are making ambitious plans for rallies, voter registration drives, attack ads, bus tours and even a multiday vigil, all intended to highlight the most controversial elements.

Upon his return to Washington early Friday, Trump described the package as “very popular,” though polling suggests that public opinion is mixed at best.

For example, a Washington Post/Ipsos poll found that majorities of U.S. adults support increasing the annual child tax credit and eliminating taxes on earnings from tips, and about half support work requirements for some adults who receive Medicaid.

But the poll found majorities oppose reducing federal funding for food assistance to low-income families and spending about $45 billion to build and maintain migrant detention centers. About 60% said it was “unacceptable” that the bill is expected to increase the $36 trillion U.S. debt by more than $3 trillion over the next decade.