President-elect Donald Trump heads a sprawling, multibillion-dollar empire and he increasingly appears unwilling to cede control, posing a serious conflict of interest and an unwise departure from past practice.

Incredible as it may seem, no law compels Trump to put his assets in a blind trust. But previous presidents have made it a point of pride to do that which was not required of them. Jimmy Carter, Ronald Reagan, George H.W. Bush, George W. Bush and Bill Clinton all voluntarily made use of blind trusts when they took office. The Obamas did not, but their modest assets at the time were not thought to pose a conflict.

Now comes Trump, possibly the wealthiest man ever to occupy the White House, with hundreds of companies and business interests that span the globe, who plans to put his adult children in charge of the Trump Organization — the same children who served on his campaign and are involved in his transition. Trump has called the arrangement a blind trust. Let's be clear: It is not, and it is arrogant for Trump to think he can hoodwink the public by saying it is.

This is not a casino deal; it's the presidency of the United States, and it's wrong to soil the office with a tawdry commingling of business interests and political power.

Equally outrageous is the defense offered by transition counsel Rudy Giuliani, who is all too familiar with ethical challenges. Giuliani's rationale is breathtakingly brazen: Trump does not need to take special action regarding his businesses because as president he is exempt from conflict-of-interest laws. Giuliani also notes that Trump does not want to deprive his adult children of the Trump empire. Meanwhile, Ivanka Trump has already begun sitting in on meetings with world leaders.

This kind of thinking is dangerously akin to that of Richard Nixon, who when asked whether he would commit an illegal act if he thought it in the best interest of the country replied: "When the president does it, that means it is not illegal."

This country can ill afford a return to that mind-set. Giuliani continues to offer up proof why Trump would be unwise to add him to his Cabinet.

The presidency, Trump will come to learn, is a demanding job that is more about sacrifice than power. It is not a job you take to enrich yourself or your offspring, and he can ill-afford even the appearance that he might be doing so.

The possibilities for conflict are so massive they are nearly unavoidable. China, accused by Trump of creating a climate change "hoax" to destroy American competitiveness, holds loans on his properties. Germany's ailing Deutsche Bank carries more than $300 million in mortgages on Trump properties. That's a lot of leverage to have on the next U.S. president. Trump gets millions of dollars from his properties in Istanbul. How could Americans be assured that would not affect his decisions regarding Turkey?

Trump must make a clean break. He should start by releasing the tax returns he kept hidden as a candidate, legally separate himself from his business interests, and pledge not to skirt federal nepotism laws by installing his son-in-law, developer Jared Kushner, in the White House as an unpaid adviser. His children should stop sitting in on meetings.

The Trump Organization may have been a family affair, but the presidency cannot be.