Trump has explicitly said he is above the law: "He who saves the country cannot break the law" is what he posted.

He pardoned people who stormed the capital, threatened gov officials, and killed police officers. Pardoning DOGE employees is child's play -- but it would never get that far because the DOJ and FBI have been purged of those not fully subservient to Trump.

Or, as JD Vance wrote, "Judges aren't allowed to control the executive's legitimate power." (https://x.com/JDVance/status/1888607143030391287). You really have to read it twice to understand just how far out that phrase is. So now it's the executive itself deciding what's "legitimate" (=conforming to the law), not the courts, whose role it is to interpret and enforce laws?

This will end badly and it will not be fun at all in the end, but it is fascinating to watch how this new wave of fascism unfolds.

Honest question: who else, internal to the executive branch, and besides the president, should be able to interpret the laws for the executive branch?

By my reading, this is a clarification that if an agency makes a significant policy change or regulation, they ought to run it by the president first.

It doesn't preclude other branches of government from checking this power.

Security clearances are based on laws, such as the ones compiled in Title 50 U.S. Code §3341.