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?

It´s executive privilege.

Explanation:

The supporter of the president´s executive privilege say that he can shield sensitive information from Congress if there´s a risk to national security, or his acts to preserve US national security exempt him from legal liability, enjoying legal immunity.

explanation:

hitler's  "rise" can be considered to have ended in march 1933, after the reichstag adopted the enabling act of 1933 in that month. president paul von hindenburg had already appointedhitler  as chancellor on 30 january 1933 after a series of parliamentary elections and associated backroom intrigues.