Ya got me, but this is essentially the same order George W. Bush issued as soon as he took office.
Best I can tell, it’s up to the Committee chair to decide - or maybe the principals can show up when they think it falls in their area (it says they “shall” attend, but that’s all).
If you want to look up the previous NSC iterations, the following excerpt gives you the four Directives and one Memorandum about the NSC makeup from the five most recent Presidents:
“With every new president comes a new memorandum or directive (and
acronym) organizing and guiding the NSC. President Obama issued
Presidential Policy Directive-1 (PPD-1); President George W. Bush issued
National Security Presidential Directive-1 (NSPD-1); President Clinton
issued Presidential Decision Directive-2 (PDD-2); and President George
H.W. Bush issued National Security Directive-1 (NSD-1). It is important
to state up front that NSPM-2 ultimately serves as the operating manual
of the NSC but it is not necessarily how national-security
decision-making will ultimately happen in practice.”
The above from a person who served as an NSC staffer under both Bush 2 and Obama.
