Rex Tillerson confronted the Trump administration’s greatest obstacle to its foreign policy this week. The faceoff took place not in Damascus or Pyongyang but Foggy Bottom.

“Now, I think it’s important to also remember that guiding all of our foreign policy actions are our fundamental values: our values around freedom, human dignity, the way people are treated,” the secretary of state told his employees. “Those are our values. Those are not our policies. They’re values.”

The former ExxonMobil CEO needing to make the distinction suggests he understands his audience.

He continued that “if you condition our national security efforts on someone adopting our values, we probably can’t achieve our national security goals or our national security interests. If we condition too heavily that others must adopt this value that we’ve come to over a long history of our own, it really creates obstacles to our ability to advance our national security interests, our economic interests.”

The partial separation of national interests from national values represents a shift from the foreign policies of Donald Trump’s two immediate predecessors and a challenge to the worldview pervasive within the State Department.

In Leading from Behind: The Obama Doctrine and the U.S. Retreat from International Affairs, Herb London contrasts the muscular internationalism of the George W. Bush administration with the soft internationalism of the Barack Obama administration. Trump offers something entirely different, and perhaps deeply offensive, to the foreign policy hands of the two previous administrations and the people addressed by his secretary of state this week.

London describes the Obama Doctrine as an “accommodationist foreign policy” reliant on the approval of international institutions. This approach often leaves the U.S. “irrelevant” on the world stage and “unreliable” to allies.

London delivers a harsh judgment on the late administration. “President Obama has been an abject failure in foreign policy,” he writes in article included in Leading from Behind that originally appeared at The American Spectator. “He has been outwitted and outplayed by Iran, Russia, China, and the Islamic State, among others. The once-heralded American military behemoth has lost its luster. Challenges that were once inconceivable occur routinely with an Obama team that seems weak and irresolute.”

Obama’s approach came as a departure from the Bush Doctrine, which stressed preemption in the wake of 9/11, viewed the extension of democracy as essential to American interests, and reserved the right to act unilaterally. “If Bush placed an unyielding faith in democracy as a source of conversion,” Leading from Behind notes, “President Obama relies instead on transnational associations, what some have described as the end of national sovereignty.” In assessing the foreign policies of both presidents, London judges that “the consequence on non-intervention, in some ways, is as bad as the consequences of intervention in Iraq.”

In his reticence to intervene and skepticism of nation building as a panacea, Trump rejects the Bush Doctrine. In his assertion of American sovereignty and disavowal of doctrinaire multilateralism, Trump similarly rejects the Obama Doctrine. He eschews the moralism inherent within the outlooks of both presidential predecessors.

London posits that Candidate Trump’s rhetoric may not necessarily match President Trump’s reality.

“Very often events take hold of stated goals,” he writes. “As a non-ideological personality, [Trump] might end up as an internationalist should Russian and Chinese imperial goals interfere with or overstep American global interests.” Indeed, the surprise strikes in Syria vindicate the author’s forecast to a great degree.

Surely circumstances play havoc on general principles and unfriendly foreign actors do not always cooperate with presidential intentions. Obama, who declared the war on terror over before terror rebutted his position, and Bush, who criticized nation building as a candidate before dedicating his presidency to it, prove this. So do Woodrow Wilson (“He kept us out of war”) and Franklin Roosevelt, who presided over relatively anemic defense budgets until World War II reoriented his thinking.

More than 100 days into the new administration, the Syrian fireworks display excepted, the Trump administration still seeks, in the words of Rex Tillerson, to “translate ‘America First’ into our foreign policy.”

How did Tillerson translate that controversial two-word phrase to State Department apparatchiks harboring prejudices towards it?

“We must secure the nation,” he says “America First” means. “We must protect our people. We must protect our borders. We must protect our ability to be that voice of our values now and forevermore, and we can only do that with economic prosperity. So, it’s foreign policy projected with a strong ability to enforce the protection of our freedoms with a strong military, and all of you that have been at this a long time understand the value of speaking with a posture of strength — not a threatening posture, but a posture of strength.”

Republicans, including the one in the White House, soon decide whether a restrained “America First” works better than an interventionist “America Headfirst.” “America First,” they uniformly believe, surely beats “America Worst.”