WASHINGTON — Geopolitics dominated Defense Secretary Jim Mattis’ appearance before the Senate Armed Services Committee on Thursday. Here are three highlights:

1. U.S. arms sales. Mattis wants Congress to add national security waivers to the law that bars U.S. arms sales to any nation that buys Russian arms: the Countering America's Adversaries Through Sanctions Act.

The law is hindering new alliances, inadvertently helping Russia, as it’s “boxing us in,” according to Mattis.

“There are nations in the world who are trying to turn away from formerly Russian-sourced weapons and systems,” Mattis said. “We only need to look at India, Vietnam and some others to recognize that. Eventually, we’re going to paralyze ourselves.”

He proposed waiver authority be granted to the secretary of state. His preference was that the administration be required to report new waivers to Congress but not seek its approval each time.

CAATSA inhibits deals with India, Vietnam and Indonesia, which he said are “trying to shift to more of our airplanes, our systems. But they’ve got to do something to keep their legacy military going.

“Every day Russia in a position basically to checkmate us with what they’re doing. It’s urgent,” Mattis said. “In the dynamics of today, issues can shift countries very, very quickly. And we want to move when we see the opportunity at the speed of relevance.”

2. Iran deal. President Donald Trump called the 2015 Iran nuclear deal “insane.” But Mattis had a softer word for it: “imperfect,” and even praised its compliance verification process as “pretty robust as far as our intrusive ability to get in” with representatives of the International Atomic Energy Agency.

Mattis’ remarks come as the administration is up against a mid-May deadline, weighing whether it will remain in the Iran nuclear agreement. Meanwhile, the French president and German chancellor are visiting Washington this week in part to persuade Trump not to pull out of the deal.

Still, Mattis downplayed the possible link between America’s withdrawal and its credibility in upcoming North Korea negotiations, pointing to North Korean leader Kim Jong Un’s unreliability in honoring agreements.

“In light of Kim’s family and himself breaking every international treaty, every agreement they’ve ever made, whether it be with the Republic of Korea or the United States, I’m less concerned with that ripple effect right now,” Mattis said.

3. Syria. Trump has sent mixed messages about the continued involvement of U.S. troops in Syria. But Mattis suggested he wants to keep a holding force in Syria to ensure the Islamic State group doesn’t reappear after most American troops leave.

If America was to leave the job to local forces before they are ready to secure the peace, “I am confident that we would probably regret it,” he said.

There will be a “reenergized effort” against ISIS on the Iraq side of the border, as French special forces are reinforcing American troops, he noted.

“Right now, we are not withdrawing,” Mattis said. “We’re continuing the fight. We’re going to expand it and bring in more regional support.”

Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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