Republican Presidential front-runner Donald Trump speaks at the Mar-A-Lago Club in Palm Beach, Fla., on Tuesday. (John Moore/Getty Images)

Donald Trump is now the clear favorite to win the Republican nomination for president. Forecasters suggest that the Democratic nominee would be favored against Trump, but Trump has a meaningful chance of winning. It’s possible that on Jan. 20, 2017, Donald Trump will be standing in front of the Capitol across from Chief Justice Roberts swearing that he will “faithfully execute the office of President of the United States.”

The Fix's Chris Cillizza explains when the GOP frontrunners stand after Super Tuesday. (Whitney Leaming/The Washington Post)

Should that happen, just how effective is Trump likely to be as a president?

The Trump brand

Trump’s appeal is directly tied to his prominent business career. Although questions remain about just how successful his companies have been (several have gone through bankruptcy court), this is politics, and image is everything. Over the past few decades, Trump’s skill at branding himself the ultimate chief executive is unrivaled. But if Trump’s supporters, and perhaps Trump himself, expect his skills in the boardroom to translate well into the Oval Office, they may be setting themselves up for profound disappointment.

Trump is not known for seeking out advice, especially from academics. But if he does gain a majority of electoral votes next November, he might want to read what many political scientists consider one of the most important books ever written on the presidency: Richard Neustadt’s “Presidential Power.”

What Truman knew about being POTUS

Neustadt, who died in 2003, was a well-respected academic who founded the Kennedy School at Harvard. His famous book is grounded in real-world experience as an aide in the Truman White House. In fact, most of Neustadt’s argument is set up by a story he recounted from the latter days of Truman’s term in office. Truman was speculating about what was about to face his successor, the former general Dwight D. Eisenhower.

“He’ll sit here,” Truman would remark, (tapping his desk for emphasis), “and he’ll say, ‘Do this! Do that!’ And nothing will happen. Poor Ike — it won’t be a bit like the Army. He’ll find it very frustrating.”

Neustadt’s point is tied to the second part of the presidential oath: the pledge to “preserve, protect, and defend the Constitution of the United States.” As Neustadt explains, the Constitution doesn’t exactly set up a separation of powers; rather, it establishes separate institutions that share powers. Most of the time, in order for presidents to accomplish something, they need the cooperation of others. This cooperation is seldom guaranteed.

Even in foreign affairs, where presidents are most often seen as independent actors, powers are shared. The Supreme Court hammered this home in a little-noticed decision last year. The case, Zivotofsky v. Kerry, involved a disagreement between Congress and the president over which branch had the final say in whether a U.S. citizen born in Jerusalem could list Israel as their place of birth on their passport.

The Court sided with the president. However, Justice Anthony M. Kennedy, writing for a six-member majority, reminded the administration that:

. . . it is Congress that makes laws, and in countless ways its laws will and should shape the Nation’s course. The Executive is not free from the ordinary controls and checks of Congress merely because foreign affairs are at issue.

Consider the Affordable Care Act, or as it should be called, “ObamaPelosiReidRobertscare”

Let’s look at how this works in practice. Clearly the Affordable Care Act is the Obama presidency’s signature achievement. Often referred to as “Obamacare,” a more accurate — though admittedly more awkward — name would be “ObamaPelosiReidcare.”

Yes, President Obama signed the bill into law, but only after some controversial parliamentary maneuvering by the Democratic leaders of the House and Senate. It is, after all, a law, and the lawmaking power is shared.

And it’s not just shared between the executive and the legislative branches. When Trump, in a recent debate, said that the Affordable Care Act “might as well be called Robertscare,” he was onto something. Often, the courts must also approve. That’s why Neustadt argued that the real power exercised by a president was the power to “persuade.”

The Obama administration’s second-most significant accomplishment might be in the area of trade. During his first term, Obama managed to get Congress to approve free trade agreements with South Korea, Panama and Colombia. The Trans-Pacific Partnership (TPP), signed by the Obama administration’s trade representative Michael Froman about a month ago, would encompass 40 percent of global GDP. Obama may not be able to persuade Congress to ratify the TPP. If he fails, he will leave office without the centerpiece of his administration’s much-vaunted “Asia pivot.”

Imagine Obama saying, “Poor Donald.”

Given how much candidate Trump has complained about U.S. trade policy, he would be wise to understand that, as president, his power to make adjustments to U.S. trade policy depends on cooperation — not only with Congress, but with other nations’ leaders.

Perhaps the author of “The Art of Deal” possesses some talent in this area. Still, it is amusing to think of Obama sitting at his desk one day in the near future saying, “Poor Donald — it won’t be a bit like running a company. He’ll find it very frustrating.”

Paul Sracic (@pasracic) is chair of the department of politics and international relations at Youngstown State University.