Which political theory has been interpreted to mean that a president can shield critical information from Congress as a result of the separation of powers?

The political theory often cited in this context is the "unitary executive theory." This theory posits that the president possesses broad authority over the executive branch, including the discretion to withhold certain information from Congress, particularly when it relates to national security or foreign affairs. Proponents argue that this separation of powers grants the president the ability to act independently in the interest of the nation, while critics contend it undermines congressional oversight. This interpretation has been a point of contention in discussions regarding executive privilege and accountability.