President Biden has wasted no time in addressing the damage of the Trump years, issuing a slew of executive orders and presidential proclamations — most of them reversing the last administration’s most controversial actions. He rejoined the World Health Organization and the Paris climate agreement, canceled a gas pipeline permit the Trump administration had approved and abolished the 1776 Commission his predecessor had set up to push a distorted view of U.S. history. But Biden’s orders on immigration most exemplified his attempt to undo Donald Trump’s legacy on Day One: He halted construction on Trump’s border wall, rescinded the infamous travel ban on people from several Muslim-majority countries and recommitted to protections for unauthorized immigrants brought to the country as children.

Like Biden’s inaugural address, these orders immediately changed the language of American government, and they suggest an ambition for bold action. But that dramatic run of reversals makes Trump’s own use of executive power appear more ephemeral than it actually was. If Biden is going to succeed, these orders must be but a prelude — necessary but not sufficient for undoing Trump’s changes, which, unlike the bluster of the man himself, are not easily set aside. The orders must be followed with concrete actions by lower-level officials who have the express authority to bring about change. And only a strong political will, sustained over time and acted upon in concert by officials throughout the bureaucracy, will truly uproot the Trump legacy so that a new one can be put in its place.

That’s because Trump’s transformations went deeper than all of his high-profile, now-rescinded executive orders. Immigration highlights the challenge for the new administration vividly. As Adam Cox and I demonstrate in our recent book, “The President and Immigration Law,” the executive’s power over immigration law does not come primarily from the sorts of decrees Trump favored but through the oversight of a vast enforcement apparatus. The trick for an administration with a dominant policy agenda is to weave high-level vision through a complex bureaucracy. And it turns out that officials of the last administration were masters of precisely that, even if Trump himself was not: His advisers understood that executive power was not just about swift, decisive action, but about tedious, concerted policy planning.

As the Migration Policy Institute has shown, the Trump-era changes to the immigration system numbered in the hundreds and consisted of dramatic reinterpretations of the laws alongside seemingly clerical changes, such as revised application forms for visas, higher fees and tighter deadlines in immigration courts — all to advance a maximalist enforcement agenda and slow down the ordinary gears of immigrant admissions. High-level White House advisers, working with knowledgeable allies in the Homeland Security and Justice departments, pushed out regulation after regulation to render asylum laws more restrictive and make it harder for noncitizens to present their case in immigration courts. Trump’s attorneys general exerted unprecedented authority to define asylum laws to severely limit claims by victims of domestic and gang violence, and to constrain immigration judges’ ability to grant relief and manage their dockets in a way that provides a semblance of due process.

The new leadership at the Department of Homeland Security has already recognized the in-the-trenches work required to sort out the mess, following Wednesday’s executive orders with a memorandum announcing that the department will conduct a top-to-bottom assessment of its enforcement policies and put removals on hold in the meantime.

Similar stories could be told about other corners of the administrative state. Executive orders alone won’t undo years of the Trump administration’s damage. In the environmental realm, for example, one scholar has referred to Trump’s legacy as “regulatory carnage.” Trump officials displaced and degraded scientific and other evidence-based analysis in areas like the environment that depend on such expertise for policy to be effective. Painstaking work will be necessary to repromulgate and build upon complex emissions rules and fuel economy standards. The same goes for a State Department whose personnel and networks have been enervated and yet must now be robust to enable the international cooperation required to tackle climate change. At the Labor Department, the Trump administration engaged in an all-out assault on workers by rescinding or reconfiguring dozens of rules designed to protect their wages, retirements and bargaining power.

Of course, the furthest-reaching and most lasting change typically comes through legislation. Biden’s decision to send a fully thought-through immigration reform bill to Congress on Wednesday demonstrates his awareness of the limits of executive action. Take the case of DACA. Advocates brilliantly succeeded in preventing the Trump administration from unwinding the program through complex procedural arguments in court. But litigants are running out of time. Texas and other states continue to press their claim that the policy amounts to executive overreach, in a lawsuit that may well culminate in a Supreme Court decision invalidating DACA.

A loss in court would make Biden’s commitment to preserving and fortifying DACA ephemeral — just as Trump’s desire to undo it was without judicial support. As the back and forth over DACA has shown us, a system that relies on the grace of the executive to forbear from enforcing the law is inherently unstable and unreliable. And so Biden’s proposed U.S. Citizenship Act of 2021 recognizes that only Congress can promise long-term security in the form of lawful status, to the “dreamers” and the millions of other unauthorized immigrants who call the United States home.

And yet, the new administration’s policy agenda will not be complete unless legislative proposals are accompanied by concerted executive action across the administrative state, and not just because ambitious legislation on any issue faces an uphill climb in a Senate with the narrowest of Democratic majorities. Even when it comes to pass, legislation emerges from a bargain, leaving issues unaddressed, introducing new concepts to be interpreted and creating new programs that demand administration. Changing the direction of our government requires not only executive vision, but also multilayered strategies that make their way through the bureaucracy and down to the ground — along with the stamina and patience to see them through.

Twitter: @cmrodriguez95