https://www.zerohedge.com/political/trumps-attack-deep-state-spectacular-and-almost-certainly-legalTrump's Attack On The Deep State Is Spectacular And Almost Certainly Legal
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First, Trump’s refusal to fund corrupt agencies: Since 1801, under the aegis of Thomas Jefferson, presidents have had a power known as 
impoundment. This means the president gets to decide how to spend—or not spend—money that Congress has allocated.
In other words, the generation that ratified the Constitution believed that this was an appropriate exercise of executive power. However, in 1974, in yet another piece of Watergate fallout, Congress enacted the “Congressional Budget and Impoundment Control Act of 1974,” which says that the president must submit to Congress his plans not to spend money.
Given the history of impoundment (the ratifying generation approved of it), it's highly unlikely that this act is constitutional. The fact that no president has yet challenged it doesn’t change this reality. Additionally, because Trump has a majority in Congress, if he were to submit his impoundment plan, the greater likelihood is that it would give him a pass. (RINOs would have a hard time explaining to voters why they want America to pay for “trans” comic books in Peru.)
Second, Trump’s ability to fire employees: Here’s a slimmed-down version of the history of presidential power in this area.
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Things changed in the 1930s when an activist Supreme Court created a new standard, which has affected (or infected) the government to this day:
 It held that if Congress designates an agency as “independent,” Congress, not the president, has the power over dismissal, with the president as its agent. This was the go-ahead to create a fourth branch of government that is neither legislative, executive, nor judicial, although, as we’ve repeatedly seen, these “independent” agencies all claim those powers.
The big issue of our day is whether these “independent” agencies are constitutional—I say they’re not because they are not one of the three branches of government established under the Constitution. Thankfully, the Supreme Court has, of late, been pulling back from the 1930s template...