Some people have referred to it as the "secret government" of the United States. It is not an elected body, it does not involve itself in public disclosures, and it even has a quasi-secret budget in the billions of dollars.
This government organization has more power than the President of the United States or the Congress, it has the power to suspend laws, move entire populations, arrest and detain citizens without a warrant and hold them without trial, it can seize property, food supplies, transportation systems, and can suspend the Constitution.
Not only is it the most powerful entity in the United States, but it was not even created under Constitutional law by the Congress. It was a product of a Presidential Executive Order. No, it is not the U.S. military nor the Central Intelligence Agency, they are subject to Congress.
The organization is called FEMA, which stands for the Federal Emergency Management Agency. Originally conceived in the Richard Nixon Administration, it was refined by President Jimmy Carter and given teeth in the Ronald Reagan and George Bush Administrations.