Rex Tillerson’s tenure as secretary of state has been tumultuous, damaging to American foreign policy and his department. And, one can reasonably speculate, more unpleasant and unsatisfying than not for Mr. Tillerson himself.

Successful secretaries of state tend to have respectful relationships with their boss. The Trump-Tillerson partnership failed miserably as the president soured on the former ExxonMobil C.E.O. and marginalized him in policymaking. A relationship in which Mr. Tillerson privately called President Trump a “moron” and Mr. Trump publicly faulted Mr. Tillerson for “wasting his time” on North Korea seemed destined to end badly.

Mr. Tillerson has approached his job more as an efficiency-driven management consultant than as the nation’s senior diplomat and spokesman to the world. He has undermined the institution of diplomacy by advocating a 30 percent cut in the State Department budget and trying to push out 2,000 career diplomats, has shown little interest in explaining American positions at home or abroad and has done little to counter the steady erosion of trust in America’s historic role as a global leader, which Mr. Trump has brought about by his indifference to old alliances and his courtship of despots and strongmen.

Yet, amid reports that Mr. Tillerson may soon be forced out of his job, the people thought to be front-runners in any shake-up of the administration’s national security team are cause for concern and, potentially, every bit as inimical to the national interest. Although other names are said to be in play, C.I.A. Director Mike Pompeo is reportedly the top choice to succeed Mr. Tillerson at State while Senator Tom Cotton, an Arkansas Republican, is a leading contender to replace Mr. Pompeo.