Michael D'Antonio is the author of the book "Never Enough: Donald Trump and the Pursuit of Success" (St. Martin's Press). The opinions expressed in this commentary are his.

(CNN) As Deputy Attorney General Rod Rosenstein appointed a special counsel to investigate the President and his associates , he imposed on Donald Trump something he has spent a lifetime avoiding -- accountability.

In a sober moment, even The Donald might admit he had it coming, though his tweet Thursday morning calling the move part of a "witch hunt" against him suggests that he still sees himself as untouchable.

In not yet four months as President, Trump has tested the limits of every institution that exists to prevent the chief executive of the United States from becoming a despot.

Congress responded with investigations of his connections to Russia . The courts rejected his unconstitutional bans on Muslim visitors. And the press has alerted the world to his countless violations of common sense and decency.

He nevertheless has thus far refused to do the job he was elected to do, preferring instead to tweet, act with reckless abandon and play a great deal of golf.

The naming of the special prosecutor, who will have enormous investigative power, was precipitated by Trump's dismissal of James Comey and the revelation that he allegedly asked the FBI director to drop his probe of the Trump campaign's possible links to Russia.

Although these two explosive stories broke within the space of a couple of days, in that same period we also heard that when the President recently entertained the Russian foreign minister and ambassador, he allegedly divulged highest-level secrets about terror threats, which were supplied by foreign partners who expected them to be protected.

Trump's lifelong practice of exploiting others and shirking responsibility guaranteed that he would indulge in the reckless behavior that has brought him, and the world, to this crisis point.

This is a man who has spent decades wounding others -- and himself -- at an astonishing rate and has responded to the various wreckages with a combination of denial and defensiveness. These classic bully characteristics have allowed him to avoid most of the repercussions of his behavior.

Before he became a national political figure, most Americans were unaware of the fact that Trump's businesses had lost at least $1 billion and perhaps as much as $6 billion during a business career he claimed was a brilliant success.

The money was supplied by investors and, since it was filtered through corporation, Trump was never held personally accountable.

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He has avoided acknowledging the pain he inflicted on people he bullied in real estate deals or cheated with exploits like the so-called Trump University. In the latter case, his business was forced to pay $25 million to settle a lawsuit , but the man was so immune to accountability that he was elected at the time when the Trump U lawsuit was widely publicized in the media.

The election campaign was, in retrospect, the ultimate Trump display of bullyboy arrogance. It began with a diatribe against immigrants, whom he categorized as drug dealers, rapists and murders. Next came the rallies, where Trump seemingly incited violence and insulted his competitors in the crudest terms: Dr. Ben Carson was compared to a child molester; Hillary Clinton was a criminal.

After being rewarded with the loyalty of those who loved the spectacle, Trump declared : "I could stand in the middle of 5th Avenue and shoot somebody and I wouldn't lose voters." This was said in Iowa, just two months after he publicly mused about how "stupid" Iowans were for actually listening to one of his GOP opponents.

Although Trump dared them to reject him, Iowans gave Trump a landslide victory, which netted him the state's Electoral College votes. In doing so, they ignored the insults and crude behavior, siding with disruptive Trump, as many bystanders who are both excited and terrified by a bully, are wont to do.

Next, the Republicans in Washington -- including many who felt he was unfit for office -- became Trump's enablers in order to enjoy the power that came with control of the House, the Senate, and the White House . In a craven display of self-loathing, Ben Carson became Trump's champion.

Winning is everything to Trump, and in his life before the presidency, he used the same limited methods -- defiance, deception, distraction -- over and over again to get what he wanted.

But hidden inside these tactics was the risk inherent in daring others to oppose him.

Never one to learn new tricks, the 70-year-old Trump has finally reached the limits of his arrogance. He has crashed into a system of law designed to save the country from someone like him. By all accounts, a man of integrity, Rosenstein has at last given a man who is devoid of this quality exactly what he has been asking for all along.