What happens when the executive branch is allowed to operate in secrecy and without constraint? This was answered in 1976, by the United States Senate Select Committee to Study Governmental Operations with Respect to Intelligence Activities, chaired by Senator Frank Church:

The natural tendency of Government is toward abuse of power. Men entrusted with power, even those aware of its dangers, tend, particularly when pressured, to slight liberty. Our constitutional system guards against this tendency. It establishes many different checks upon power. It is those wise restraints which ‘keep men free. In the field of intelligence those restraints have too often been ignored.

The three main departures in the intelligence field from the constitutional plan for controlling abuse of power have been: (a) Excessive Executive Power.

In a sense the growth of domestic intelligence activities mirrored the growth of presidential power generally. But more than any other activity, more even than exercise of the war power, intelligence activities have been left to the control of the Executive.

For decades Congress and the courts as well as the press and the public have accepted the notion that the control of intelligence activities was the exclusive prerogative of the Chief Executive and his surrogates. The exercise of this power was not questioned or even inquired into by outsiders. Indeed, at times the power was seen as flowing not from the law, but as inherent, in the Presidency.

Whatever the theory, the fact was that intelligence activities were essentially exempted from the normal system of checks and balances. Such Executive power, not founded in law or checked by Congress or the courts, contained the seeds of abuse and its growth was to be expected.

(b) Excessive Secrecy.

Abuse thrives on secrecy. Obviously, public disclosure, of matters such as the names of intelligence agents or the technological details of collection methods is inappropriate. But in the field of intelligence, secrecy has been extended to inhibit review of the basic programs and practices themselves.

Those within the Executive branch and the Congress who would exercise their responsibilities wisely must be fully informed. The American public, as well, should know enough about intelligence activities to be able to apply its good sense to the underlying issues of policy and morality.

Knowledge is the key to control. Secrecy should no longer be allowed to shield the existence of constitutional, legal and moral problems from the scrutiny of all three branches of government or from the American people themselves.

(c) Avoidance of the Rule of Law.

Lawlessness by Government breeds corrosive cynicism among the people and erodes the trust upon which government depends.

Here, there is no sovereign who stands above the law. Each of us, from presidents to the most disadvantaged citizen, must obey the law. As intelligence operations developed, however, rationalizations were fashioned to immunize them from the restraints of the Bill of Rights and the specific prohibitions of the criminal code. The experience of our investigation leads us to conclude that such rationalizations are a dangerous delusion.

As you can see, the Committee pointed its finger at the government, the public and the press.  Attitudes needed to be changed all around.

This is yet another parallel between modern times and the the Vietnam War era (I realize that that war had ceased by 1976).  Many other parallels were detailed by the movie “War Made Easy.”

The above passage is analyzed in more detail at Common Dreams.