Here are the parts of the Fire and Fury book that relate directly to immigration:

...On December 14, a high-level delegation from Silicon Valley came to Trump
Tower to meet the president-elect, though Trump had repeatedly criticized the
tech industry throughout the campaign. Later that afternoon, Trump called
Rupert Murdoch, who asked him how the meeting had gone.
“Oh, great, just great,” said Trump. “Really, really good. These guys really
need my help. Obama was not very favorable to them, too much regulation. This
is really an opportunity for me to help them.”
“Donald,” said Murdoch, “for eight years these guys had Obama in their
pocket. They practically ran the administration. They don’t need your help.”
“Take this H-1B visa issue. They really need these H-1B visas.”
Murdoch suggested that taking a liberal approach to H-1B visas might be
hard to square with his immigration promises. But Trump seemed unconcerned,
assuring Murdoch, “We’ll figure it out.”
“What a fucking idiot,” said Murdoch, shrugging, as he got off the phone.

...But the first step in the new Trump administration had to be immigration, in
Bannon’s certain view. Foreigners were the ne plus ultra mania of Trumpism. An
issue often dismissed as living on the one-track-mind fringe—Jeff Sessions was
one of its cranky exponents—it was Trump’s firm belief that a lot of people had
had it up to here with foreigners. Before Trump, Bannon had bonded with
Sessions on the issue. The Trump campaign became a sudden opportunity to see
if nativism really had legs. And then when they won, Bannon understood there
could be no hesitation about declaring their ethnocentric heart and soul.
To boot, it was an issue that made liberals bat-shit mad.
Laxly enforced immigration laws reached to the center of the new liberal
philosophy and, for Bannon, exposed its hypocrisy. In the liberal worldview,
diversity was an absolute good, whereas Bannon believed any reasonable person
who was not wholly blinded by the liberal light could see that waves of
immigrants came with a load of problems—just look at Europe. And these were
problems borne not by cosseted liberals but by the more exposed citizens at the
other end of the economic scale.
It was out of some instinctive or idiot-savant-like political understanding that
Trump had made this issue his own, frequently observing, Wasn’t anybody an
American anymore? In some of his earliest political outings, even before
Obama’s election in 2008, Trump talked with bewilderment and resentment
about strict quotas on European immigration and the deluge from “Asia and
other places.” (This deluge, as liberals would be quick to fact-check, was, even
as it had grown, still quite a modest stream.) His obsessive focus on Obama’s
birth certificate was in part about the scourge of non-European foreignness—a
certain race-baiting. Who were these people? Why were they here?
The campaign sometimes shared a striking graphic. It showed a map of the
country reflecting dominant immigration trends in each state from fifty years ago
—here was a multitude of countries, many European. Today, the equivalent map
showed that every state in the United States was now dominated by Mexican
immigration. This was the daily reality of the American workingman, in
Bannon’s view, the ever growing presence of an alternative, discount workforce.
Bannon’s entire political career, such as it was, had been in political media. It
was also in Internet media—that is, media ruled by immediate response. The
Breitbart formula was to so appall the liberals that the base was doubly satisfied,
generating clicks in a ricochet of disgust and delight. You defined yourself by
your enemy’s reaction. Conflict was the media bait—hence, now, the political
chum. The new politics was not the art of the compromise but the art of conflict.
The real goal was to expose the hypocrisy of the liberal view. Somehow,
despite laws, rules, and customs, liberal globalists had pushed a myth of more or
less open immigration. It was a double liberal hypocrisy, because, sotto voce, the
Obama administration had been quite aggressive in deporting illegal aliens—
except don’t tell the liberals that.
“People want their countries back,” said Bannon. “A simple thing.”

...Bannon meant his EO to strip away the liberal conceits on an already illiberal
process. Rather than seeking to accomplish his goals with the least amount of
upset—keeping liberal fig leaves in place—he sought the most.
Why would you? was the logical question of anyone who saw the higher
function of government as avoiding conflict.
This included most people in office. The new appointees in place at the
affected agencies and departments, among them Homeland Security and State—
General John Kelly, then the director of Homeland Security, would carry a
grudge about the disarray caused by the immigration EO—wanted nothing more
than a moment to get their footing before they might even consider dramatic and
contentious new policies. Old appointees—Obama appointees who still occupied
most executive branch jobs—found it unfathomable that the new administration
would go out of its way to take procedures that largely already existed and to
restate them in incendiary, red-flag, and ad hominem terms, such that liberals
would have to oppose them.
Bannon’s mission was to puncture the global-liberal-emperor-wears-no-
clothes bubble, nowhere, in his view, as ludicrously demonstrated as the refusal
to see the colossally difficult and costly effects of uncontrolled immigration. He
wanted to force liberals to acknowledge that even liberal governments, even the
Obama government, were engaged in the real politics of slowing immigration—
ever hampered by the liberal refusal to acknowledge this effort.
The EO would be drafted to remorselessly express the administration’s (or
Bannon’s) pitiless view. The problem was, Bannon really didn’t know how to do
this—change rules and laws. This limitation, Bannon understood, might easily
be used to thwart them. Process was their enemy. But just doing it—the hell with
how—and doing it immediately, could be a powerful countermeasure.

...Bannon got Stephen Miller to write the immigration EO. Miller, a fifty-five-
year-old trapped in a thirty-two-year-old’s body, was a former Jeff Sessions
staffer brought on to the Trump campaign for his political experience. Except,
other than being a dedicated far-right conservative, it was unclear what particular
abilities accompanied Miller’s political views. He was supposed to be a
speechwriter, but if so, he seemed restricted to bullet points and unable to
construct sentences. He was supposed to be a policy adviser but knew little about
policy. He was supposed to be the house intellectual but was purposely unread.
He was supposed to be a communications specialist, but he antagonized almost
everyone. Bannon, during the transition, sent him to the Internet to learn about
and to try to draft the EO.
By the time he arrived in the White House, Bannon had his back-of-the-
envelope executive order on immigration and his travel ban, a sweeping,
Trumpian exclusion of most Muslims from the United States, only begrudgingly
whittled down, in part at Priebus’s urging, to what would shortly be perceived as
merely draconian.
In the mania to seize the day, with an almost total lack of knowing how, the
nutty inaugural crowd numbers and the wacky CIA speech were followed,
without almost anybody in the federal government having seen it or even being
aware of it, by an executive order overhauling U.S. immigration policy.
Bypassing lawyers, regulators, and the agencies and personnel responsible for
enforcing it, President Trump—with Bannon’s low, intense voice behind him,
offering a rush of complex information—signed what was put in front of him.
On Friday, January 27, the travel ban was signed and took immediate effect.
The result was an emotional outpouring of horror and indignation from liberal
media, terror in immigrant communities, tumultuous protests at major airports,
confusion throughout the government, and, in the White House, an inundation of
lectures, warnings, and opprobrium from friends and family. What have you
done? Do you know what you’re doing? You have to undo this! You’re finished
before you even start! Who is in charge there?

...The negotiation to bring Mexican president Enrique Peña Nieto to the White
House had begun during the transition period. Kushner saw the chance to
convert the issue of the wall into a bilateral agreement addressing immigration—
hence a tour de force of Trumpian politics.

...Jared and Ivanka believe, said Bannon, that if they advocate prison reform
and save DACA—the program to protect the children of illegal immigrants—the
liberals will come to their defense. He digressed briefly to characterize Ivanka
Trump’s legislative acumen, and her difficulty—which had become quite a
White House preoccupation—in finding sponsorship for her family leave
proposal. “Here’s why, I keep telling her: there’s no political constituency in it.
You know how easy it is to get a bill sponsored, any schmendrick can do it. You
know why your bill has no sponsorship? Because people realize how dumb it is.”
In fact, said, Bannon, eyes rolling and mouth agape, it was the Jarvanka idea to
try to trade off amnesty for the border wall. “If not the dumbest idea in Western
civilization, it’s up there in the top three. Do these geniuses even know who we
are?”