The national security adviser is one of the most important positions in the U.S. government, and by extension, in global politics. That person is responsible for providing the president guidance on national security issues, not only by offering advice but by marshaling a process to ensure that decisions on those matters reflect the best thinking of the entire government of the United States. The ability to manage that process is as important as, if not more so than, the subject matter expertise that he or she brings to the job.
Given the importance of the position, the speed with which U.S. President Donald Trump is going through national security advisers is alarming. This week, Trump either fired John Bolton, his national security adviser, or received his resignation — the uncertainty is typical of the chaos and confusion that marks this White House. Bolton was Trump's third national security adviser.
Bolton's departure confirms two important trajectories in U.S. national security decision-making. First, Trump is his own man on national security matters and is not going to be "managed" by the bureaucracy. Second, the president is more inclined to diplomacy and deal-making than belligerence. That latter swing is most likely the cause of the break between Trump and Bolton.