There is no reason to doubt that in seeking reelection, President Trump will consider once more breaking or skirting laws or ethical limits to win. He has already proclaimed a willingness to accept campaign support from a foreign government, retreating only somewhat under public pressure. He rejected an official recommendation that senior aide Kellyanne Conway be dismissed for serial violations of the legal limits on political activity by federal government employees under the Hatch Act. He has repeatedly suggested that the Department of Justice prosecute his political opponents. And to read about the way Trump conducted his business affairs is to appreciate that he will likely run his campaign no differently—with a “whatever it takes” mentality, disdainful of legal and moral constraints.

It may be tempting to imagine that Trump, and Trump alone, is the source of the problem—that once he’s gone, the problem will go with him. But in his unapologetic embrace of a politicized executive branch, he is feeding off, while also aggressively building on, a feature of the powerful modern presidency: presidents’ use of executive branch powers and resources for partisan political purposes, particularly the waging of their reelection campaigns.

Presidents have long attempted to exploit to the fullest the political advantages of incumbency. At the same time, there are legal limits and associated norms that function to keep the federal government from operating as an arm of the executive’s campaign organization and party. But Donald Trump, never keen on limits, has begun to challenge them frontally, unlike any president before him.

There are three predominant sources for the politically weaponized executive branch, all of which arise out of the structure of American politics and the centrality and power of the presidency.

First, the institutional party system is weak and presidents do not depend on their national and state parties to run their campaigns. Instead, their own reelection committees carry the weight of the organizational effort and the parties become annexes to the president’s own campaign apparatus. But all that these organizations plan for and do remains subject to discussion with and approval from 1600 Pennsylvania Avenue. As a result, it is only through the White House’s central involvement that the campaign can achieve the necessary coordination with the principal’s wishes and the president can control his or her own campaign.

Second, in a highly fractured media environment, the White House has a peerless advantage in breaking through the noise. It can “drive” the message in a way that parties and reelection committees cannot. The chair of a campaign or of the Republican National Committee cannot command attention in the way that the president or the White House communications staff can. This has long been true, but in the absence of a dominant “mainstream” media, and with round-the-clock digital campaign coverage, the president who takes advantage of his or her perch in the White House can achieve exceptional control of the headlines and shape campaign coverage.

Third, in competitive elections, no candidate or party fails to seize every possible advantage in the search and effective deployment of resources. The executive branch can support the campaign in numerous ways irresistible to the president-as-candidate. Rulemakings of considerable constituency interest can be launched—or abandoned. Discretionary grants of federal funds can be targeted to key voter targets or states. The president can trumpet new legislative proposals to Congress, or showcase global leadership with unilateral foreign policy or trade initiatives. All of this is familiar in the strategies and practices of past administrations. As long ago as the Carter presidency, complaints were brought unsuccessfully to the courts about the strategic use of federal power for campaign purposes.

Politics is politics: It “ain’t beanbag.” The political use of incumbency is common to all modern presidencies. There have remained limits, transgressed most notoriously in the Nixon era. But because Richard Nixon and his associates took their improper electioneering to an extreme—no one would defend burglaries as “politics as usual”—it was possible to believe that Watergate was the product of a particular pathology, to dismiss it as extraordinary and to discount or ignore other factors that might lead future presidents seeking reelection to accelerate down the same path.

It did not take long for this belief to be proved false. First Jimmy Carter and then Ronald Reagan set up a special and specifically designated political office within the White House to assist with campaign planning, among other tasks. Funded by the White House budget, it was first named the Office of Political Affairs and Personnel. Later, in the Reagan administration, it became the White House Office of Political Affairs (OPA). The campaign politics of the presidency had come to be institutionalized.

The question presented by more overt White House partisan political activity was never whether the president and his staff breached a duty or expectation by failing to steer entirely clear of partisan politics. It has been widely understood that, as a practical matter, the president as leader of his party—and often a candidate for reelection—is a political figure and neither can nor should leave the White House and cross the street to private office space to conduct campaign activity or planning. But the president cannot entirely dispense with senior staff support for this activity. The issue is how far this staff support extends down the chain and throughout the executive branch, and with how much latitude staff are able to draw on taxpayer resources and official influence for this purpose.

The story of the OPA is one more episode in the ongoing struggle over this issue, and it brings to light the significance of what is playing out in the Trump administration.

On a fairly limited level, the challenge presented by an OPA—or by any other White House political activity—is enabling presidents to engage with their campaign and party while avoiding any direct, more than de minimis commitment of government resources for this purpose. Presidents have room under the rules to receive, to comment on and direct campaign or party programs and planning, and to communicate and coordinate effectively with political allies. An OPA could, for example, maintain regular contact with party organizations and political allies to ensure consistency of messaging in the course of a reelection campaign or midterm congressional election. But the executive branch cannot be an affiliate of the campaign, defraying with taxpayer dollars expenses that the president’s reelection committee or the party should bear. This is a misuse of funds appropriated for official purposes, and federal law prohibits it.

For example, the White House cannot provide office space for campaign aides on the reelection committee or party payroll. No staff can solicit campaign contributions on federal property or with government equipment or the assistance of government-paid support personnel. Parties and candidates have to reimburse the government for any campaign travel by the president or the vice president, on Air Force One or Two, on their behalf. During Bill Clinton’s 1996 reelection campaign, for example, questions were raised about the Clinton campaign’s alleged use of White House facilities, such as the Lincoln Bedroom, to support its fundraising program, and congressional Republicans pursued that issue after the election as part of a broader investigation into the financing of Clinton’s 1996 campaign.

Another danger, overlapping with the first, is the abuse of official power to achieve political advantage. The Hatch Act was designed in part to prevent government officials from pressuring those in federal service to contribute campaign funds or otherwise support the political aims of the party in power. The law prohibits the abuse of “official authority or influence for the purpose of interfering with or affecting the result of an election.” For the most part, partisan activity in the executive branch is permissible only off premises and outside normal hours, and those engaging in it (other than the president and vice president, who are exempt) are barred from using their titles or government positions to convert what they may do in a personal capacity into the impression of a campaign initiative that is government approved or sponsored.

The law carves out an exception for the time committed to campaign matters by senior White House staff and Senate-confirmed cabinet and other officials. On the theory that their jobs require them to be “on duty” at all times and wherever they happen to be, they are provided with more of an accommodation for politics in the workplace. They may conduct politics in official space and during regular working hours so long as any identifiable use of government resources is reimbursed. Reimbursement from a private source is required only for increases in the cost to the government over and above “any costs that the Government would have or have incurred regardless of whether the activity was political.”

In 2011, the Office of Special Counsel (OSC), an independent agency charged with the enforcement of the Hatch Act, issued a report finding pervasive violations associated with the OPA’s activities in the George W. Bush administration. The OPA had conducted extensive briefs of executive branch agency officials on the status of the 2006 midterm elections, urged their “volunteer” support for the Republican campaign effort, and coordinated the travel of administration officials to states and congressional districts to support Republican candidates in competitive races. In some cases, the OPA was acting as a clearinghouse for requests from campaigns for administration “surrogate” support at clearly political events. In other cases, the travel was for supposedly “official” purposes, but the objective was to target these appearances and actions for maximum election-year benefit.

The OSC concluded that the “OPA has come to represent the centralization of electoral politics in the White House”: In 2006, it was nothing less than a “partisan political organization.” The OSC found that most of the OPA staff and virtually all of the agency officials did not qualify for the exemption from the rule prohibiting political activity on premises and during regular business hours.

This was in certain respects a restrictive reading of what the Hatch Act allowed. Some of what the OPA did in the Bush administration was not unique to that presidency, and not all lawyers familiar with the Hatch Act had previously read the rules the same way. I was White House counsel at the time and among the lawyers who took note of what seemed a new direction in the OSC’s interpretation of the rules. But there was no question that the OSC’s position was the last word on the subject and established a requirement for Hatch Act compliance.

In any event, shortly before the OSC’s issuance of the report, the Obama administration had announced the closing of the OPA as the 2012 reelection campaign was launched and headquartered in Chicago. Three years later, in 2014, the administration created a new Office of Political and Strategic Affairs but defined its function more narrowly as a channel of information to the president on political matters. Administration spokespersons announced that the new office would not have an operational role in supporting the administration’s strictly political projects.

Now the Trump administration is taking the very different course of mounting a frontal challenge to OSC interpretation and enforcement of Hatch Act limits. In the wake of the OSC’s recommendation for Kellyanne Conway’s dismissal, the White House counsel attacked the OSC on the primary jurisdictional issue of whether that office may promulgate rules or guidance at all. It has further taken direct issue with the OSC’s interpretation of when an official like Conway is expressing a constitutionally protected personal opinion or when that official is engaged in impermissible electioneering in her official capacity. The details for present purposes do not matter. What is striking is the Trump administration’s choice to undermine the capacity of the OSC to address apparent Hatch Act violations in the future or even to clarify the law’s requirements.

The same president who has questioned why he cannot direct the law enforcement judgments of the Justice Department was most unlikely to accept the strictures that the OSC sought to impose. The Hatch Act is an obstacle to the efficient conduct of a full-scale White House-directed political campaign. So are the norms of Justice Department independence and distance from partisan politics that the president has questioned. Prior administrations facing these limits have felt compelled to acknowledge them, even when there have been disagreements about their application. The Obama administration adjusted to the OSC’s more stringent reading of the rules. In 2007, the Bush administration denied charges that it had dismissed U.S. attorneys unwilling to use their power to advance partisan political projects, but, critically, it did not dispute that any such motivation would have been wrong. Trump, by contrast, seems intent on defending pervasive partisanship in the operation of the executive branch.

Even when Trump is forced to cede some ground to these rules and norms, his acknowledgment is grudging and highly qualified, and it seems unrealistic to read too much into it. He backtracked somewhat on his announcement that he would accept political opposition research from a foreign government and not report the contact to the FBI. But he suggested that he would still review the information to determine if it was “incorrect,” and he said nothing about refraining from using it in his campaign.

In this respect, Trump may have been sending a message—intentionally or unintentionally—to those in Moscow and other foreign capitals who are potentially ready if not eager to help him in his reelection campaign. The danger here is potentially starker than in the 2016 presidential campaign, when Trump was just a candidate and his prospects for success were widely underestimated. Foreign powers must deal with the president and do so regularly, and the incentive for them to help him in his campaign—and the levers a president possesses to extract this information—is considerably greater than in the case of a long-shot, nonincumbent candidate. Moreover, Trump may be emboldened to seek or accept help from this direction by Robert Mueller’s decision to decline to find campaign finance violations arising out the Trump campaign’s active solicitation of support from the Russian government. While Trump and his campaign associates would have to know that, after 2016 and the Mueller investigation, they will face closer scrutiny of any such political ties to foreign interests, the legal risks they are prepared to take may simply turn on how much value they attach to the information they think they can get.

No small part of the dangers of these developments can be chalked up to the immorality and disregard for law that characterizes this presidency. But the steady concentration of power in the presidency, and the president’s singular role within a weak institutional party system, invites this abuse. It is inevitable that each president has to judge how far he or she will push the legal and ethical limits in putting the power of incumbency and the resources of the federal government to partisan political use.

Donald Trump is evidently prepared to go far and push hard. He is now working to legitimate, by effectively legalizing and normalizing, the weakening of these constraints. He may be dismantling these guardrails and undermining norms only in his own interest, but presidents who follow him may appreciate and take advantage of the opportunities he has afforded them.