There's little to stop Trump wreaking havoc as president.

By Chris Berg.

There are supposed to be checks and balances that would prevent Donald Trump doing too much damage as US president. But these have been eroded and an era of “imperial presidency” means we should be worried, writes Chris Berg.

The prospect of a Donald Trump presidency shouldn’t be as worrying as it is.

The United States constitution is specifically designed to prevent presidents from doing too much damage. But the carefully, intelligently designed checks and balances built into the American system of government have been so eroded over the last century that a president Trump could do the sort of harm the founding fathers wished to prevent.

The issue is not so much Trump’s policies. I complained in January that Trump was no conservative – particularly on trade – but then again, he wouldn’t be the first non-conservative president. In fact, policy-by-policy he looks like the most moderate candidate in the Republican field; the temporary ban on Muslim immigration to the United States notwithstanding.

Nor is being a “populist” a crime. Trump would hardly be the first president who got to power by telling voters only what they wanted to hear.

What's worrying about Trump is his unpredictability, his disregard for any boundary between truth and self-serving fiction, his unbridled narcissism, his instability, and his apparent desire to pursue his enemies with the tools of high office.

He sees himself as a "strong man" - hence his apparent affinity with other strong men like Vladimir Putin. And at this stage it is easy to imagine a chain of events that puts him in the White House.

The American founding fathers were aware that a democratic political system could turn out a person like Trump. The Federalist Papers, the essays written in 1787 and 1788 to argue the case for the constitution, were motivated by a theory of human nature "that men are not to be trusted with power because they are selfish, passionate, full of whims, caprices, and prejudices," in the words of one scholar.

Hence in the famous Federalist Paper 51, James Madison argued that power must be separated between different branches of government. Each branch - the executive, the legislature, and the judiciary - would vie for power against the others.

"Ambition must be made to counteract ambition," Madison wrote. The institutional structures of the American republic would ensure that a strong man or narcissist, were they elected to the presidency, would be constrained by the other branches.

Yet those structures have been systematically degraded over the past century. The presidency has accumulated power at the expense of the legislature.

As the word implies, the executive's intended function is to execute the laws passed by Congress. But the modern presidency has carved out an enormous field of action where it can operate virtually without the oversight of the other branches. The historian Arthur M Schlesinger Jr. called this the "imperial presidency".

The most obvious example of the imperial presidency is foreign policy. Under the text of the constitution, only the Congress has the power to declare war. But the last war to be declared by Congress was World War II. Since then presidents have been asserting almost unlimited, unilateral power over military engagement and interventionism. The upshot is that, contrary to the founders' intentions, the president can effectively send the country to war on nothing but their own counsel.

Trump says he now opposes the invasion of Iraq, but he also wants to take Islamic State's oil. Whatever strategy he implements to do so, the combined forces of the United States military are in practice at his complete disposal.

Just as concerning is the power the president can wield over public policy. The original idea behind Western liberal democracy is that policy is made by the legislature as they negotiate and pass law. But the growth of regulation as a substitute for statute has vested more and more power in the executive government.

In 2014 federal departments, agencies and commissions passed 16 new regulations for every one law the Congress passed. As the economist Tyler Cowen wrote last month: "If there were a president who wished to pursue vendettas, the regulatory state would be the most direct and simplest way for him or her to do so." Having the vindictive Trump responsible for all this is dangerous.

The shift from a constrained presidency to an imperial presidency has been cultural as well. In his book The Rhetorical Presidency, Jeffrey K Tulis argues that the presidency has assumed a symbolic role not envisioned by the founders.

Voters - and the press - describe one of the key requirements of the office as "leadership". Yet as Tulis points out, this was not what the founders hoped. The Federalist Papers had only a dozen mentions of the word leader. All but one were disparaging.

During the 20th century, the presidency became about words as much as administration - presidents were rated on their personalities and ability to channel popular sentiment.

Trump is the apotheosis of this change: a demagoguing narcissist who is all surface and shine. But all democracies are vulnerable to such populist figures. The founders knew that. If only their great institutions had been maintained.

Chris Berg is a senior fellow with the Institute of Public Affairs. His latest book, The Libertarian Alternative, will be published by Melbourne University Publishing in May. Follow him at twitter.com/chrisberg

This post originally appeared on the ABC.

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