Question

what does this mean "If men were angels, no government would be necessary. If angels were to govern men, neither external nor internal controls on government would be necessary."

Answer 1

In Federalist 51, James Madison wrote, “If men were angels, no government would be necessary. If angels were to govern men, neither external nor internal controls on government would be necessary.” Significant reforms to Congress and the Executive Branch are necessary because we are not governed by angels, but by men (and women) with all their human limitations.
The Congress of the United States is often referred to as the greatest legislative body in the world. The Founders recognized the supremacy of the Congress in our system of government by establishing the structure, qualifications for membership, and powers in the very first article of the Constitution. Thus, Article I begins:
“All legislative Powers herein granted shall be vested in the Congress of the United States, which shall consist of a Senate and House of Representatives.”
While the first three articles of the Constitution vest unique powers in three separate institutions of government -- legislative, executive and judicial branches -- they do not confer any power to a federal government.
At the same time, the Founders envisioned a limited not an unlimited form of self-government. Accordingly, the Constitution sets up a series of checks and balances, even on the expansive powers of the Congress. The Constitution itself is intended to restrain the powers of the federal government over the people by enumerating the powers of the government and making an express reservation of all other powers to the states or to the people.
The most important power of the Congress is the power of the purse. It thus becomes the prudential responsibility of the Congress to determine how and where to spend the taxpayer’s money.
Over the years, Senator Tom Coburn of Oklahoma has issued his annual "Wastebook" showing the profligacy of the politicians in Congress when dealing with someone else's money -- the taxpayers -- to which they are entrusted.
Congress has, however, vastly exceeded all reasonable and prudent spending limits and has done so without clearly expressing the enumerated constitutional power that permits such excessive spending. This excessive spending results in some measure from the creation of more and more government programs and departments that require bigger and bigger bureaucracies without accountability from Congress. We have finally reached the point that Benjamin Franklin said we would: “When the people find they can vote themselves money, that will herald the end of the republic.”
Thus, Congress must be reformed to ensure: (1) that all legislation is enacted pursuant to a power enumerated in the Constitution; (2) that Congress reduce spending to reasonable levels to achieve the principles of the limited government established by the Founders; and (3) hold agencies accountable for the effective management of government programs. Moreover, it is within Congress’s purview to reform government. c: