For the first time in our turbulent history, a sitting member of a presidential Cabinet, Attorney General Eric Holder, has been held in criminal contempt of Congress by the House of Representatives for failing, when subpoenaed, to provide key documents in an aborted gun-trafficking investigation.

Stripping that historic contempt of any meaning, the Justice Department, of which Holder is the boss, refuses to prosecute him. That’s because Holder’s boss, President Barack Obama, has characteristically invoked executive privilege to keep those documents sealed.

Since 9/11, we have become a nation in which the president frequently acts as a king, without acknowledging the legislature and the courts.

So, in the wake of the huge attention being paid to the Supreme Court’s upholding of Obamacare, Eric Holder remains our chief law enforcement officer — and Obama’s regal role in keeping Holder out of court as a defendant has been almost entirely overlooked.

With the presidential election fast approaching in November, voters on both sides have almost entirely lost sight of the high crimes committed by Holder and Obama against one of the most profound constitutional rights guaranteed to every one of us in the Fifth Amendment:

Nor shall any person “be deprived of life, liberty, or property, without due process of law.”

As King George III and his British troops found out, there is no place for a king in the United States of America. Yet, on March 5, before students at the Northwestern University School of Law, Attorney General Holder loftily explained why President Obama was well within the Constitution in assassinating three American citizens as terrorism suspects in Yemen without a trace of due process. The king had spoken.

As George Washington University Law professor Jonathan Turley, a constitutional law sharpshooter, puts it: “He insisted that a ‘careful and thorough executive branch review of the facts in a case amounts to “due process““ ‘ (“Obama’s Kill Policy,” jonathantur​ley​.org, March 7).

Turley then spears Holder by saying that his “new definition of ‘due process’ was perfectly Orwellian.”

And I urge any of you intending to vote to continue the rule of King Obama to dig this warning from Turley:

“What Holder is describing is a model of an imperial presidency that would have made Richard Nixon blush. If the president can kill a citizen, there are a host of other powers that fall short of killing that the president might claim, including indefinite detention of citizens.”

The president already has that power in the National Defense Authorization Act for Fiscal Year 2012.

Turley continues: “Thus, by asserting the right to kill citizens without charge or judicial review, Holder (and Obama) has effectively made all of the Constitution’s individual protections of accused persons matters of presidential discretion.”

As if that weren’t frightening enough to those of us whom the Declaration of Independence speaks for, Turley emphasizes how zealously the administration keeps these royal killings classified:

“Already, the administration has successfully blocked efforts of citizens to gain review of such national security (assassination) powers or orders. Not only is the list of citizens targeted with death kept secret, but the administration has insisted that courts do not play a role in the creation of or basis for such a list.”

As Turley writes, even when the family of one of the assassination targets “tried to challenge Obama’s kill order, the federal court declared that (the target) would have to file for himself — a difficult task when you are on a presidential hit list.”

Entering this grim conversation is Tom Engelhardt, an author and a Fellow at the Nation Institute:

“Be assured of one thing: whichever candidate you choose at the polls in November, you aren’t just electing a president of the United States; you are also electing an assassin-in-chief. The last two presidents may not have been emperors or kings, but they — and the vast national-security structure that continues to be built-up and institutionalized around the presidential self — are certainly one of the nightmares the founding fathers of this country warned us against” (“Praying at the Church of St. Drone,” tomdis​patch​.com, June 5).

Mitt Romney, why aren’t you saying anything about our presidents having metamorphosed themselves into killing machines of the Constitution? At the very least, shouldn’t the voters know how you would disarm the presidency of the power to unilaterally kill Americans who are suspected of “association” with terrorism — and have no chance of defending themselves in court?

To accomplish this, sir, you need to educate the citizenry on specifically how the Constitution forbids this. Because of your seemingly inadequate education in this area, I suggest you invite Ron and Rand Paul — the two members of Congress who consistently and insistently refer to constitutional liberties — to discuss with you those parts of the Constitution that have been forgotten by the previous two administrations.

In this way, you can promise the electorate that the time of a president as assassination-in-chief is over, and you can assure the nation that, if elected, your office will no longer indefinitely imprison Americans.

Also, during your education from Ron and Rand Paul, you might become engaged in other parts of the Constitution that will considerably improve your choices of nominees for newly available Supreme Court vacancies. Your place in history will then far excel those of George W. Bush and Barack Obama.