The Trump National Security Council keeps the members Congress requires by law — the President, Vice President, and the Secretaries of State, Defense, Energy, and Treasury — while Trump has used his authority to reshape almost everything around them. Across two non-consecutive terms starting in 2017 and 2025, he has rewritten the council’s membership rules twice, cycled through five national security advisors, cut staff roughly in half, and dissolved standing directorates covering pandemic preparedness and cybersecurity coordination.
Who Sits on the Council
The National Security Act of 1947 created the council as the president’s primary forum for coordinating foreign policy and defense.1Office of the Historian. National Security Act of 1947 Federal law fixes six permanent members: the President, Vice President, Secretary of State, Secretary of Defense, Secretary of Energy, and Secretary of the Treasury.2Office of the Law Revision Counsel. 50 USC 3021 – National Security Council Those seats do not change from one administration to the next.
Everything else does. The statute lets the president invite additional officials — the Director of National Intelligence, the Chairman of the Joint Chiefs of Staff, the National Cyber Director, and others — to attend and participate. Each administration uses that authority through an executive memorandum issued early in the term, and Trump has issued one on the first day of both his terms.
Day-to-day operations run through the National Security Advisor, formally titled Assistant to the President for National Security Affairs. The job sits inside the White House staff and requires no Senate confirmation, so the president can hire and fire without Congress. That feature explains much of what has happened since 2017.
The First-Term Membership Fight: NSPM-2 and NSPM-4
On January 28, 2017, Trump issued National Security Presidential Memorandum-2, defining the Principals Committee — the senior deliberative group that shapes policy before it reaches the president. The listed attendees included the Secretaries of State, Treasury, Defense, and Homeland Security, the Attorney General, the Chief of Staff, the National Security Advisor, and the Homeland Security Advisor.3Congressional Research Service. The National Security Council – Background and Issues for Congress
Two features drew immediate criticism. Chief Strategist Steve Bannon received a permanent seat on the Principals Committee, a slot traditionally held by cabinet officials and career national security professionals. At the same time, the Director of National Intelligence and the Chairman of the Joint Chiefs were left off the regular attendee list and invited only when their specific expertise was needed. Former officials from both parties argued the arrangement injected political staff into national security deliberations while pushing intelligence and military leadership to the margins.
The reversal came fast. On April 4, 2017, NSPM-4 replaced the earlier memorandum. Bannon was removed from the Principals Committee. The DNI and Chairman of the Joint Chiefs were restored as regular attendees of both the full council and the Principals Committee, alongside the CIA Director and the U.S. Ambassador to the United Nations. NSPM-4 also formalized the Deputies Committee structure for lower-level interagency coordination.4Federal Register. National Security Presidential Memorandum-4 – Organization of the National Security Council, the Homeland Security Council, and Subcommittees The council’s membership returned to roughly the shape used by earlier administrations.
The 2025 Reorganization
Trump issued NSPM-1 on January 20, 2025, restructuring the council for the second term. The memorandum again merged certain NSC and Homeland Security Council functions, with the two bodies convening jointly on topics agreed in advance by the National Security Advisor and the Homeland Security Advisor.
Five Advisors in Eight Years
The person who runs the council for the president has changed five times since January 2017.
Michael Flynn (January 22 – February 13, 2017)
A retired lieutenant general and former director of the Defense Intelligence Agency, Flynn resigned 24 days into the job after reporting revealed he had discussed U.S. sanctions on Russia with the Russian ambassador before Trump took office and then misled Vice President Mike Pence about those conversations. He later pleaded guilty to making false statements to the FBI and was pardoned by Trump in November 2020.
H.R. McMaster (February 20, 2017 – April 9, 2018)
An active-duty Army lieutenant general, McMaster ran the most conventional version of the Trump-era NSC.5Congress.gov. The Honorable Herbert Raymond McMaster He emphasized a structured interagency process, moving policy options through formal committee review before decisions reached the president. His tenure overlapped with the NSPM-4 reset that restored traditional membership.
John Bolton (April 9, 2018 – September 10, 2019)
Bolton came in from a career in law and senior government appointments, including a year as U.S. Ambassador to the United Nations.6U.S. Department of State. Bolton, John R. He moved the council away from large interagency meetings toward smaller, more direct consultations with the president. Around May 2018, under his tenure, the NSC’s Directorate for Global Health Security and Biodefense was dissolved and its staff reassigned to units covering weapons of mass destruction and international organizations. The decision drew intense scrutiny when COVID-19 emerged in early 2020.
Robert O’Brien (September 18, 2019 – January 20, 2021)
An attorney who had been serving as Special Presidential Envoy for Hostage Affairs, O’Brien focused on what the administration called “rightsizing” the council. He shrank staff and pushed policy-development authority back to the State Department and the Department of Defense rather than letting the NSC operate as a parallel policy shop.
Michael Waltz (January 20 – May 1, 2025)
A former congressman and Army Green Beret, Waltz lasted about three and a half months. His removal and the events surrounding it are covered below.
Marco Rubio (May 1, 2025 – present, interim)
Secretary of State Marco Rubio was named interim National Security Advisor after Waltz’s removal, an unusual arrangement that places the country’s top diplomat in a dual role.
Staff Cuts and Dissolved Directorates
The NSC staff numbered over 200 people at the start of the first term, many of them detailed from other federal agencies. By January 2021, that number had been cut roughly in half under O’Brien, mostly through attrition and non-renewal of detail assignments rather than layoffs. Additional layoffs followed roughly three weeks after Waltz’s departure in 2025.
Two directorate-level changes had specific consequences. The Global Health Security and Biodefense directorate was dissolved in May 2018. The Cybersecurity Coordinator position was eliminated the same month, with responsibility shifted to the senior director of the NSC’s Cyber directorate. A 2020 Government Accountability Office review found the council never clearly defined what those cybersecurity responsibilities included, failed to identify resources needed for most activities in the National Cyber Strategy, and set up no process for monitoring whether agencies were actually carrying the strategy out.7U.S. GAO. Cybersecurity – Clarity of Leadership Urgently Needed to Fully Implement the National Strategy
Signalgate and the 2025 Shake-Up
In March 2025, a Signal group chat was created to discuss planned U.S. military strikes against Houthi targets in Yemen. The chat included roughly 18 senior officials, among them the Secretary of Defense, the Secretary of State, the Vice President, and the Director of National Intelligence. Jeffrey Goldberg, editor-in-chief of The Atlantic, was inadvertently added to the group and read the discussion in real time. Messages contained operational details about targets, weapons, and attack timing. The NSC confirmed the chat was authentic.
The incident raised two legal issues. Federal records laws require government employees using commercial messaging apps to forward or copy those messages to official government accounts. And Department of Defense rules restrict classified discussions to government-approved secure networks, not commercial apps.
Waltz was removed on May 1, 2025 and nominated to serve as U.S. Ambassador to the United Nations. Reporting indicated the immediate catalyst was not the Signal breach itself but a policy disagreement: Waltz had taken a hawkish line on Iran that clashed with Trump’s interest in pursuing diplomacy first.
Why the Structure Keeps Moving
The statutory core of the council does not move. The Vice President and the Secretaries of State, Defense, Energy, and Treasury sit on it because federal law says so.2Office of the Law Revision Counsel. 50 USC 3021 – National Security Council The working structure around that core — who else attends the Principals Committee, how large the staff runs, which directorates exist, and whether the council develops policy or merely coordinates it — is set by presidential memorandum and reshaped by each new advisor.
Under Trump, the consistent thread has been a preference for a leaner council with fewer independent policy functions. The execution has been anything but consistent: two full membership rewrites in the first term alone, dissolved directorates whose absence became visible during later crises, five advisors in eight years, and a sitting Secretary of State now doing the job on an interim basis. When the advisor changes that often, institutional knowledge leaves with each departure, relationships with foreign counterparts reset, and policy processes built over months are scrapped and rebuilt.