A young boy with his mother attend a rally by United We Dream, an immigrant youth-led organization, protesting the recent immigration raids nationwide at LaFayette Square in front of the White House on Feb. 11. (Linda Davidson/The Washington Post)

The Trump administration’s attempts to translate the president’s hard-line campaign rhetoric on immigration into reality have run into two major roadblocks: the complexity of reshaping a sprawling immigration system and a president who has not been clear about how he wants to change it.

In his first four weeks in office, President Trump has sought to use his executive powers to punch through Washington’s legislative and bureaucratic hurdles and make quick progress on pledges to crack down on illegal immigrants and tighten border control.

But Trump has been vague about his goals and how to achieve them and his aides have struggled to interpret his orders.

The resulting turmoil has included a successful legal challenge halting his immigration travel ban, fears among congressional Republicans over the White House’s more extreme measures and widespread anxiety among immigrant communities across the country.

The latest flash point erupted Friday over reports that the Department of Homeland Security was considering mobilizing 100,000 National Guard troops to help round up millions of unauthorized immigrants in 11 states, including some such as Colorado and Oregon far from the southern border.

President Trump said at a press conference Thursday that deciding the fate of illegal immigrants brought to the U.S. as children is “one of the most difficult subjects I have.” (Jabin Botsford/The Washington Post)

The disclosure surprised state officials who oversee the troops and rattled immigrant rights advocates, who have accused federal authorities of exploiting fuzzy White House edicts to frighten vulnerable populations. Trump aides quickly distanced the White House from a memo that federal authorities called a “very early draft” of an implementation plan for Trump’s early executive orders that had not been seen or approved by DHS Secretary John Kelly.

“That is 100% not true,” press secretary Sean Spicer told reporters. “There is no effort at all . . . to utilize the National Guard to round up illegal immigrants.”

[Trump calls the news media ‘the enemy of the American people’]

Some immigration hard-liners viewed the leak of the memo to the Associated Press, which first reported on it, as evidence that anonymous bureaucrats were intent on undermining the administration.

Trump has faced pockets of resistance within the government to his immigration orders, including the ill-fated travel ban on all refugees and on immigrants from seven majority-Muslim countries that former acting attorney general Sally Yates said she would not defend in court. Although Trump fired her, the order was later suspended by a federal judge.

Trump has promised to put forward a new travel ban order next week.

To border control hawks, the president’s bumpy start has fostered a sense that a White House stocked heavily with political newcomers is learning the hard way just how difficult amending immigration policies can be. Both the Obama and George W. Bush administrations unsuccessfully pursued sweeping comprehensive reform legislation that failed to win congressional approval.

A section of the border fence in Nogales, Ariz.,is seen on February 17, 2017, on the US/Mexico border. (Jim Watson/AFP/Getty Images)

Despite his “Archie Bunkerisms that he was deporting everyone” during the campaign, Trump and his aides are “still getting their sea legs on immigration,” said Mark Krikorian, executive director of the Center for Immigration Studies, which pushes for lower immigration levels. “They’re starting to realize that it takes time to turn an aircraft carrier around.”

On the other side, immigrant rights advocates pointed to a series of episodes as evidence that federal agents are overstepping their bounds to accommodate the wishes of a president who at one point campaigned on plans for a nationwide “deportation force.”

In one recent case, an undocumented woman seeking a protective order from an abusive boyfriend was arrested by immigration agents at a Texas courthouse.

Among Trump’s earliest executive orders were measures to vastly expand the pool of immigrants who were priorities for deportation and a move to revive a program started by the George W. Bush administration that would deputize local police with immigration enforcement powers.

“There are clear signs that this administration is, in fact, going on a manhunt,” said Marielena Hincapié, executive director of the National Immigration Law Center. She called the administration’s tactics “deeply troubling — we believe unlawful.”

[Federal immigration raids net many without criminal records, sowing fear]

Within the West Wing there is a sharp ideological split among the president’s senior advisers over just how far to go on enforcement measures. Strategist Stephen K. Bannon, policy director Stephen Miller and other hard-liners have advocated for forceful restrictionist policies in keeping with Trump’s campaign rhetoric, while others such as Chief of Staff Reince Priebus remain wary of the potential political fallout from the most severe measures.

Preibus, the former Republican National Committee chairman, oversaw a 2013 report that said the party must embrace comprehensive immigration reform that included legalization measures to make inroads within the fast-growing Latino population.

Their disagreements over how to proceed have been accentuated by indecision from Trump himself. The president — who vowed to “get them all out!” during the campaign — has equivocated on a promise to “immediately terminate” an Obama administration program that has granted work permits to hundreds of thousands of immigrants who entered the country illegally as children.

Trump had derided the Deferred Action for Childhood Arrivals (DACA) program, which President Obama created through executive authority in 2012, as an unconstitutional “executive amnesty.”

But at a news conference Thursday, Trump called the fate of the program “one of the most difficult subjects I have” and vowed to “show great heart” as he deliberates over the program’s fate.

“I have to deal with a lot of people, don’t forget. And I have to convince them what I’m saying is right,” Trump said. “I find it very, very hard doing what the law says exactly to do and, you know, the law’s rough. . . . It’s very, very rough.”

[Trump lashes out at ‘so-called judge’ who temporarily blocked travel ban]

One of the people Trump will have to persuade is Rep. Steve King (R-Iowa), a conservative on immigration who was one of his earliest campaign supporters. King praised some of the president’s early moves to ramp up enforcement raids, but he said he’s been meeting regularly with like-minded “rule-of-law conservatives” to discuss Trump’s delays on ending DACA.

Trump’s presidency “pivots on whether he keeps this promise,” King said. “So that means you simply cannot legalize people that are here illegally and you cannot ratify an edict of President Obama that is blatantly unconstitutional.”

Immigration lawyers said they are uncertain about what to advise their clients. Although DHS continues to process DACA applications, advocates were jolted by the reports this week that a 23-year-old Mexican man in Seattle who is covered by the program was arrested during an enforcement raid.

The detention came after enforcement actions in several cities netted 683 immigrants. The man’s lawyers have denied allegations from authorities that he has gang ties.

“I’m going to watch it carefully, and I’m also going to see if other DACA recipients are targets,” said Patrick Taurel, an immigration lawyer in Washington with clients in the program. “If that happens, it could be death by thousand cuts. Rather than issue a new executive order terminating a very popular program and a very sympathetic program, he could effectively end it by creating fear.”

To Stuart Anderson, executive director of the nonpartisan National Foundation for American Policy, the Trump administration’s early missteps threaten to erode its credibility on the president’s signature issue.

“It makes people highly suspect of even more reasonable measures that might be able to get more support,” Anderson said. “It basically starts to make all their policies on immigration radioactive.”

Thomas Gibbons-Neff, Ed O’Keefe and Sandhya Somashekhar contributed to this report.