As President Trump nears the 100-day benchmark, it’s a good moment to examine the relationship that has evolved between the mercurial and inexperienced commander in chief and his unflappable defense secretary, Jim Mattis.

It’s an unlikely partnership, but so far it mostly seems to work. Trump may have relatively few domestic-policy accomplishments to show after three months, but he can take credit for selecting a generally solid national-security team and for listening to its advice.

Traveling with Mattis last week in the Middle East, I had a chance to watch the delicate balancing act between a media-obsessed White House and a national-security leadership that mostly would be happy to stay out of the news.

During his meetings in Saudi Arabia, Egypt and Israel, Mattis focused on alliance issues. But the big running stories last week were about symbolic displays of U.S. military power by the aircraft carrier USS Carl Vinson, and by dropping a massive weapon in Afghanistan whose nickname, “Mother of All Bombs,” was catnip for journalists. Mattis struggled to adapt to this ever-shifting information space, and his messaging wasn’t always clear.

(Reuters)

Mattis is mildly eccentric by military standards, with his penchant for studying Roman philosophy in Latin and suggesting reading lists for his troops. But like every successful Marine and Army general, he is fundamentally a team player who moves with a group, rarely in isolation.

What that has meant in practice is that Mattis has bonded with Trump’s other key foreign policy advisers: Secretary of State Rex Tillerson, national security adviser H.R. McMaster, Homeland Security Secretary John Kelly and CIA Director Mike Pompeo. This is a strong, self-confident group; there’s little of the infighting that characterizes Trump’s domestic advisers.

Mattis’s closest link, interestingly, may be with Tillerson, the ExxonMobil chief-turned-diplomat. Mattis believes that U.S. foreign policy became overmilitarized in recent years and that a strong State Department voice is essential.

The national-security process worked well in the two-day planning and execution of a missile strike this month on a Syrian airfield. Within hours of the Syrian chemical weapons attack on its people, Mattis was framing options drawn from a list of contingency plans. The Pentagon prepared for the possibility that Russia would respond. Planners predicted an 85 percent success rate for the United States; it turned out to be closer to 95 percent.

One puzzle for Mattis these days is navigating a kaleidoscopic world at a time when the public (or, at least, the media) seeks monochromatic answers. Mattis noted in an interview during the trip that Tillerson had offered a nuanced explanation of Iranian actions (complying with the nuclear agreement but meddling in the region), but coverage had focused on the negative. Policymakers sometimes need to “hold two contrary ideas in equipoise,” he explained. “Our world is not black and white.”

An example of the interplay between diplomatic and military issues is the strategy for taking Raqqa, the Islamic State’s self-proclaimed capital in eastern Syria. Trump has claimed to have a “secret plan” for victory, but the actual policy debate remains complicated and unresolved. The U.S. Central Command recommended a quick move to capture Raqqa, led by a force commanded by Syrian Kurds. The problem is that Turkey regards these Kurdish fighters, known as the YPG, as a deadly threat — and on Tuesday even bombed two YPG camps.

While respecting Centcom’s recommendations, and its sense of urgency, Mattis was persuaded by Tillerson and others to conduct a more careful review of policy. A quick hit on Raqqa that enraged Turkey might prove to be a tactical success but a strategic setback. The policy debate continues (though officials said Turkey would probably be warned against any more bombing of YPG positions).

What Mattis and the other former commanders bring to Trump’s national-security table, perhaps paradoxically, is a wariness of overly hasty military commitments. In the debate about stopping North Korea’s nuclear program, for example, Pentagon planners understand that the thriving metropolis of Seoul could become a gruesome, Stalingrad-like battlespace in an ill-planned conflict.

Discussing what he called the “ghastly” situation in Syria, Mattis voiced concern that “we are seeing the re-primitivization of war,” with use of chemical weapons and the bombing of children, hospitals, churches and other once-forbidden targets. “We’ve got to hold people accountable,” he insisted.

But how? A hidden drama of these first 100 days has been the interaction between the foreign policy team and a White House that’s just beginning to think about how to use U.S. power in a dangerous world.

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