New White House Chief of Staff John F. Kelly talks with President Trump after being privately sworn in during a ceremony in the Oval Office on July 31, 2017. (AP Photo/Evan Vucci)

President Trump reportedly caught most of his White House advisers and Cabinet secretaries off guard last week by announcing he intends to slap steep tariffs on the steel and aluminum imports on all of the United States’ trading partners. Trump’s decision is the latest reminder that one of his most consequential decisions last year was to hire retired Gen. John F. Kelly as his chief of staff.

Trump hired Kelly in the wake of policy fiascos, White House infighting and a general sense of a presidency on the rocks. In his eight months on the job, Kelly has sought to improve White House operations. But with unprecedented turnover among Trump’s top aides — much of it instigated by Kelly — and a tempestuous president, Kelly has struggled to keep Trump’s presidency on keel.

Five key things help explain why Kelly struggles to manage the White House chaos.

1. His boss won’t cooperate

Kelly has sought to impose greater discipline over White House decision-making and messaging. But Trump seems unwilling or incapable of sticking to organizational routines or exercising self-discipline, and he appears to bristle when he perceives that Kelly is “managing” him.

This leads to recurring high-profile disputes between Trump and Kelly. Trump tweets or states a controversial position or belief. Kelly walks backs or clarifies Trump’s statement. The president responds by implicitly or publicly rebuking his chief of staff. The media discusses whether  Kelly’s days in the White House are numbered.

For example, two months ago during discussions with legislators on Capitol Hill, Kelly reportedly described Trump’s campaign statements on immigration as “uninformed,” and described the president’s views on building a border wall as “evolving.” The next morning Trump tweeted:

Pundits immediately speculated that an angry Trump was searching for Kelly’s replacement. But Trump then publicly reaffirmed his support for his chief of staff.

2. Some wounds are self-inflicted

Critics often point out that Kelly’s wounds can be self-inflicted, suggesting that his years in the military left him ill prepared to address the political dimension of his job. Examples abound, such as when he accused undocumented immigrants of being too lazy to sign up for protections afforded by the Deferred Action for Childhood Arrivals program and appeared to back staff secretary Rob Porter after accusations of abuse by Porter’s two ex-wives.

As former Bill Clinton chief of staff Leon Panetta remarked: “John is a great Marine . . . but he is not a politician, and one thing he lacks is the ability to look at the big political picture and understand what you should and shouldn’t say as chief of staff.”

3. Campaigning and governing demand different skill sets

In many ways, Kelly faces difficulties that are endemic to the position. Consider that President Barack Obama’s button-down White House was the antithesis of Trump’s freewheeling approach. However, Obama went through five chiefs during his two terms as president, including three during his first term.

George W. Bush is an exception to this pattern: His first chief, Andrew Card, served for six years before leaving of his own accord, and Card’s successor finished out Bush’s second term. But Bush’s predecessor Bill Clinton also saw high turnover, with four chiefs across his eight years as president. Both George H.W. Bush and Ronald Reagan White Houses experienced similar rates of change.

Why so much turnover? Kathryn Dunn Tenpas and I show that presidents often initially choose their White House aides, including chief of staffs, from individuals who have proved their mettle on the campaign trail.

But skills prized by campaigns tend not to translate well to governing. Stephen K. Bannon, the Trump campaign strategist who briefly reprised that function in the White House, is a case in point. Trump appointed Bannon to ensure that he fulfilled campaign promises, but Trump fired Bannon shortly after Kelly’s appointment as chief of staff.  Bannon later conceded that “In many ways, I think I can be more effective fighting from the outside for the agenda President Trump ran on. ”

4. The chief of staff faces irreconcilable demands

Presidents typically task chiefs of staff with two competing functions: protecting the president’s time, their most precious asset, by streamlining the White House organization and also ensuring the president is exposed to multiple and potentially contradictory sources of political and policy advice. As my colleague Amy Yuen and I demonstrate in our research, it is very difficult to do both.

In the modern era, as White House staffs have expanded in size and internal complexity, chiefs have prioritized centralizing power to maximize administrative efficiency. But as the president’s operating environment has become more contentious, the cost is a less open presidency. Carried too far, such efforts can isolate presidents from much-needed input and advice.  Moreover, presidents may worry that their chief White House aide is usurping their decision-making authority. If media reports are accurate, that fear is one factor at the root of Trump’s rumored frustration with Kelly.

5. There is a solution if the president wants one

As Yuen and I show, presidents gain informational advantages by distributing White House staff authority across two or more political and policy advisers and pitting them against one another in a competitive advising process, rather than siloing advisers by function under a dominant chief of staff. Competitive advising forces policy and political disputes to the president, rather than allowing them to be settled by a politically unaccountable chief of staff or by lower-level aides.

For this approach to succeed, a president has to be able to handle dissent among his advisers and tolerate the unavoidable negative media coverage that staff disagreements produce. This is particularly so when aides use the media to take on rivals and to pressure their boss to choose their side.

For their part, chiefs must be willing to manage this open competition, rather than stifle it, even if it looks like they are not fully in charge of White House operations. Eight months into his tenure, it is not clear whether Kelly is willing or able to manage such a structure. Nor can we be sure that the president would let him. But the fate of Trump’s presidency rests in large part on whether he and Kelly grasp the impact of organization on presidential success.

Matthew J. Dickinson is Professor of Political Science at Middlebury College, and author of the Presidential Power blog.  His current research project builds on his first book, “Bitter Harvest: FDR, Presidential Power and the Growth of the Presidential Branch” to examine the evolution of the White House staff in the modern era.