WASHINGTON — As part of their big tax bill, Republicans in Congress are pumping billions of dollars into President Donald Trump’s mass deportation and border security plan with nearly 20,000 new officers, stark new $1,000 in fees on migrants seeking asylum and $46.5 billion for a long-sought border wall.

Tuesday launched the first of back-to-back public hearings as House Republicans roll out the fine print of what Trump calls his “big, beautiful bill” — which is focused on $5 trillion in tax breaks and up to $2 trillion in slashed domestic spending. But it also pours some $300 billion to beef up the Pentagon and border security as the Trump administration says it's running out of money for deportations.

House Speaker Mike Johnson is pushing to have the bill wrapped up by Memorial Day and then send it to the Senate, which is drafting its own version.

“We are on track,” Johnson, R-La., said at his weekly news conference.

This was always expected to be the hard part, where Republicans who have control of the House and Senate begin to fill in the difficult details of what, until now, has simply been a framework for Trump's tax package at the cornerstone of the GOP's domestic agenda.

As Trump rounds his 100th day in office, the GOP’s stiff immigration provisions come as Americans are showing unease with the president's approach, with just half saying he's focused on the right priorities. The White House is battling high-profile court cases after it mistakenly deported a Maryland man to El Salvador and, over the weekend, Trump's team rounded up countless immigrants, including foreign-born parents who were deported with their American-born toddlers and small children in tow.

Democrats are fighting back in the House and Senate, and the halls of public opinion, but as the minority party in Congress, they have little ability to stop the forward march of the package.

Instead, they used Tuesday's hearings to try to shame Republicans into rethinking their approach.

“Do a little soul searching before you vote for this,” said Rep. Bennie Thompson of Mississippi, the top Democrat on the Homeland Security Committee, at one point during the debate.

Central to the Homeland Committee's section of the legislation is $46.5 billion to revive construction of Trump's wall along the U.S.-Mexico border, with some 700 miles of “primary” wall, 900 miles of river barriers, and more.

There's also $4 billion to hire an additional 3,000 new Border Patrol agents as well as 5,000 new customs officers, and $2.1 billion for signing and retention bonuses.

Democrats kept the committee in session for hours, submitting some three dozen amendments to change the package. They all failed.

Among the first Democratic amendments offered was from Rep. Troy Carter of Louisiana to prohibit the use of funding to deport American children. Another from Rep. Seth Magaziner of Rhode Island would stop the money from being used to send Americans to foreign prisons.

“What world are we living in?” Magaziner asked.

He said allowing Republicans to “keep trampling on rights, soon everyone's rights” will be under threat.

Chairman Rep. Mark Green, R-Tenn., as he gaveled the committee open, said, “It is critical that the Republican majority do what the people elected us to do.”

The committee approved its bill on a party-line vote.

For the first time, the U.S. under the legislation would impose a $1,000 fee on migrants seeking asylum — something the nation has never done.

Experts said the new fee on asylum seekers would put the U.S. on par with a few others, including Australia and Iran.

And that's not all. The Judiciary Committee is expected to meet Wednesday on its $110 billion section of the package.

There would be new fees on various other legal paths to entry, including a $3,500 fee for those sponsoring unaccompanied children to enter the U.S., a $2,500 penalty if sponsors of unaccompanied children skip court appearances and a $1,000 fee for individuals paroled into the U.S.

Overall, the plan is to remove 1 million immigrants annually and house 100,000 people in detention centers. It calls for 10,000 more Immigration and Customs Enforcement officers and investigators.

Meanwhile, the House Armed Services Committee started drilling down Tuesday into its section of the package, with some $100 billion in new spending, including some $5 billion for border security.

But the hearing became tangled by questions from Democrats over funding for Ukraine, Trump's plan for a big military parade and calls for Hegseth to be fired or resign.

Rep. Chrissy Houlahan, D-Pa., a veteran herself, offered an amendment that would prohibit the provisions from going into effect until Hegseth “is no longer Secretary of Defense.”

Democratic Rep. Seth Moulton of Massachusetts, a combat veteran, had an amendment to prevent money on Trump's parade, which is planned for June in Washington, saying there shouldn't be a military parade for a “draft dodger,” a reference to Trump's medical deferral from Vietnam War-era service.

And Rep. Sara Jacobs, D-Calif., proposed halting any money for a make-up studio for the Pentagon secretary. It was reported that Hegseth, a former Fox News host, sought such a room for his appearances.

Hours later, the Republican-led panel wrapped up and approved its bill.

Other portions of the GOP legislation are still a work in progress, including the provisions on tax breaks for individual filers, and spending cuts to Medicaid, food stamps and other programs.

Those proposals are expected to be unveiled next week, though that timeline could slip. Once the nearly dozen committees wrap up their work, the entire package will be assembled into the “big” bill for a final vote in the House. And then it's sent to the Senate.