That power which had both the purse and the sword, had the government of the whole country, and might extend its powers to any and to every object.
No branch of government should ever be able to combine the power of the sword with the power of the purse.
The power of the purse is the only real power of government.
The House of Representatives cannot only refuse, but they alone can propose the supplies requisite for the support of the government. They, in a word, hold the purse: that powerful instrument by which we behold in the in the history of the British constitution an infant and humble representation of the people, gradually enlarging the sphere of its activity and importance, and finally reducing, as far as it seems to have wished, all the overgrown prerogatives of the other branches of the government.
The power of the purse always prevails.
We've got the power of the purse in the Congress.
We've got our own power - the power of the purse.
A government may only govern so long as the people, through their representatives, vote it the money to carry on.
One way or another ... the CIA is making a lot of extra money the citizen's aren't supplying, and that money gives the agency an undesirable, possibly dangerous independence of Congressional control.
In an ironic precursor to the Iran-Contra scandal to come a decade later:
That this privilege of giving or of withholding our monies is an important barrier against the undue exertion of prerogative, which if left altogether without control may be exercised to our great oppression; and all history shews how efficacious is its intercession for redress of grievances and re-establishment of rights, and how improvident would be the surrender of so powerful a mediator
One of the responsibilities of Congress is the power of the purse, but there is also oversight. In order to have proper oversight, you have to have agency administrators, directors, and secretaries of those agencies speak frankly and about the facts.