> Almost all federal departments and agencies derive their authority from acts of Congress.
Partially, as we need to be precise in our language.
Congress can design an agency, determine what powers it has, determine agency procedures and fund agencies.
It's up to the President to execute the law within those boundaries, including selecting the head of that agency (with Senate approval), and determining how the agency executes the law which can be incredibly broad if Congress wasn't proscriptive.
Thus the authority to execute the laws is delegated to the President by the Constitution who then delegates that power to the head of the agency which acts on the Presidents behalf.
More broadly, the Supreme Court has made clear that the Constitution imposes important limits on Congress’s ability to influence or control the actions of officers once they are appointed. Likewise, it is widely believed that the President must retain a certain amount of independent discretion in selecting officers that Congress may not impede. These principles ensure that the President may fulfill his constitutional duty under Article II to take [c]are that the laws are faithfully executed.9
https://constitution.congress.gov/browse/essay/artII-S2-C2-3...
> More broadly, the Supreme Court has made clear that the Constitution imposes important limits on Congress’s ability to influence or control the actions of officers once they are appointed.
No they did the opposite when they overruled Chevron. They said Congress cannot delegate that amount of its plenary power to the executive.
This of course lays the whole thing bare. When it comes to regulating markets or companies, or minority rights, conservatives think the president has no power. But when it comes to immigration or Christian social issues, the president is all powerful. This translates into laughable double standards like "the Biden admin even sending a single email to Twitter is pressure and censorship, but Trump suing media organization after media organization for defamation to the tune of billions of dollars is not pressure and not censorship". None of this is principled; it's entirely us vs them.
> More broadly, the Supreme Court has made clear that the Constitution imposes important limits on Congress’s [and the President’s] ability to influence or control the actions of officers once they are appointed.
Improved on that, just a tad, for this discussions context. Not disagreeing.
Without that balance Congress couldn’t delegate anything with any expectation of its will being carried out.
And the President couldn’t ensure the agency acted competently and with respect to the President’s good faith understanding of the agency’s guiding laws.
With the courts ready to step in to settle any differences.
Agencies can only work reliably with the differing participations and limitations of all three roles.
As with all expressions of law.