Defense Secretary Jim Mattis told the House on Tuesday that he was once a skeptic about maintaining ICBMs in the nation's nuclear triad, but he has changed his mind since joining the Trump administration.
Mattis said he now believes that Intercontinental Ballistic Missiles with Multiple Independently Targetable Re-entry Vehicle (MIRV) warheads in silos across the Northwest provide a "strong deterrent to anyone who decided they wanted to employ nuclear weapons against us."
At a House hearing on the Nuclear Posture Review (NPR), Mattis was responding to questions from Rep. Mac Thornberry, R-Texas, chairman of the House Armed Services Committee, about the evolution of his thinking on the nation's defenses against nuclear attack.
"When you assumed office, you were a skeptic on some aspects of our nuclear triad, our nuclear deterrence," Thornberry told Mattis. "How has your thinking evolved? It looks like there was a change, or some evolution -- why?"
"I think that's a fair statement," Mattis said in response. "I came in wanting to challenge just about everything," including the ICBM component of the nuclear triad of long-range bombers, ICBMs, and ballistic missile submarines.
"It was a little rough on the staff," he said of his demands for evidence on the capabilities and costs of the deterrent as he decided whether to support going ahead with the plan for modernization of each leg of the triad that was initiated under the administration of President Barack Obama.
There are varying estimates on the costs of the modernization, but the nonpartisan Congressional Budget Office has put the cost of the Obama administration's plan at $1.2 trillion over 30 years.
The Trump administration's NPR also calls for the development of two new nuclear weapons -- a new "low-yield" ballistic missile for submarines and a new Submarine Launched Cruise Missile (SLCM).
As first reported by The Washington Post, Mattis, a four-star Marine general who retired in 2013, had little involvement in nuclear policy in his more than 40 years in uniform. The nuclear deterrent was more the concern of the Air Force and the Navy.
As a civilian in 2015, Mattis characteristically put the issue bluntly in testimony to the Senate Armed Services Committee, asking, "Is it time to reduce the Triad to a Diad, removing the land‐based missiles?"
In his review before signing off on the NPR, Mattis told the House hearing Tuesday that he now considers all three legs of the triad to be vital to the nation's defense.
"I looked at the triad piece by piece and the elements of each leg of the triad. I was especially attentive to the Intercontinental Ballistic Missile force," he said.
He concluded that ICBMs are "a stabilizing element that would be a strong deterrent" in combination with the air and sea legs of the triad.
Air Force Gen. Paul Selva, vice chairman of the Joint Chiefs of Staff who testified with Mattis at the HASC hearing, also endorsed maintaining and modernizing each leg of the triad.
"Nuclear weapons pose the only existential military threat to our nation," Selva said. "Therefore, there is no higher priority for the joint force than fielding all the components of an effective nuclear deterrent to deter potential adversaries from nuclear attack on any scale."
-- Richard Sisk can be reached at Richard.Sisk@Military.com.