What Trump's first 100 days in office could look like

President-elect Donald Trump and his allies have already articulated ambitious plans for his first 100 days in office.

He has promised on Day 1 — within the first few hours in fact — to close the U.S. border with Mexico and launch the largest domestic deportation operation in American history.

Trump has promised to gut President Biden's climate subsidies and resume energy exploration, including offering tax breaks to oil, gas and coal producers.

"We're going to drill, baby, drill," Trump said in late October at his rally at Madison Square Garden in New York City. "And I will terminate the 'green new scam' and will cut your energy prices in half, 50%, within one year from Jan. 20."

Trump's main goal is to unwind Biden's policies and resume where he left off after his first term in office.

Trump will face obstacles enacting mass deportations

It's not going to be easy.

While presidents have broad powers over immigration, for example, there are real operational, legal and political challenges to carrying out mass deportations.

Groups like the American Immigration Council estimate it would cost billions of dollars for Trump to implement his deportation plan. It could also have a dramatic impact on the economy if industries such as construction, hospitality and agriculture lose masses of workers.

There is also a resource challenge. U.S. Immigration and Customs Enforcement already must pick and choose where to focus its limited resources.

Carrying out mass deportation would require a massive increase in manpower to arrest and deport millions of people a year.

His allies have been busy preparing executive orders

For months, allies have been working to prepare a series of executive orders that would help Trump carry out his agenda.

Republican allies say Trump should quickly reimpose his Schedule F executive order, which would reclassify a large chunk of federal staff members as at-will employees.

Doing so would pave the way for federal civil service workers to be replaced with others, including political partisans more invested in carrying out his policies.

Opponents see it as an effort to weaken the guardrails meant to ensure a nonpartisan bureaucracy.

Trump will also face pushback from Democratic opponents in Congress, as well as from civil liberties groups, such as the American Civil Liberties Union, which say they will be prepared.

They have been dusting off their own playbooks from the first Trump administration and have promised to use the courts to fight Trump.

The ACLU even published a memo this summer outlining how it would counter some potential abuses.

"Donald Trump has already threatened to abuse his power in these ways," the ACLU states in the memo. "He plans to leverage the DOJ [Department of Justice] and other governmental agencies to indict political opponents, replace civil servants and traditionally apolitical appointees with individuals willing to do his bidding regardless of legal and normative structures, and demand pledges of loyalty from civil service employees."

Republicans say they'll work "aggressively" for his agenda

Trump's allies in Congress, including House Speaker Mike Johnson, R-La., have promised to act quickly and "aggressively" to advance the president-elect's agenda. Control of the House has not yet been called, but Republicans have flipped the Senate in their favor.

That agenda includes extending Trump's 2017 Tax Cuts and Jobs Act, regulatory reform and reviewing energy policy.

"As I told President Trump, I said, 'Mr. President, you could be the most consequential president of the modern era because we have to fix almost everything,'" Johnson told reporters in October. "And it begins first with securing the border, which the American people demand and deserve. Right after that, we get straight to the economy."