From the U.S. Government Accountability Office, www.gao.gov Transcript for: The Nuclear Strategic Triad Description: Audio interview by GAO staff with Joe Kirschbaum, Director, Defense Capabilities and Management Related GAO Work: GAO-16-740: Nuclear Weapons: DOD Assessed the Need for Each Leg of the Strategic Triad and Considered other Reductions to Nuclear Forces Released: September 2016 [ Background Music ] [ Narrator: ] Welcome to GAO's Watchdog Report, your source for news and information from the U.S. Government Accountability Office. It's September 2016. Since the 1960s, the United States has deployed nuclear weapons by land, air, and sea. This combination of intercontinental ballistic missiles, nuclear capable bomber planes, and ballistic missile submarines is known as the strategic triad. A team led by Joe Kirschbaum, a director in GAO's Defense Capabilities and Management team, recently looked at the Department of Defense's reviews of the strategic triad and nuclear forces more generally. Jacques Arsenault sat down with Joe to talk about what they found. [ Jacques Arsenault: ] For starters, can you explain what the nuclear triad is and how it came about? [ Joe Kirschbaum: ] The nuclear triad really comprises the delivery vehicles, the planes, the other vehicles that carry nuclear weapons, the warheads, the bombs. And it came about in the 1960s. No one really contemplated in the '50s and up right up to the '60s that we needed a triad, three types of delivery vehicles. That was never intended. It kind of developed that way because that's the way the military services developed vehicles to carry nuclear weapons. And the three legs of the triad, as it were, are made up of strategic bombers, heavy bombers, to carry bombs. A land-based ballistic missiles, intercontinental ballistic missiles, ICBMs, and sea-based ballistic missiles carried on nuclear submarines. As the triad itself developed, the thinking behind the purposes for which we have three legs developed and those have to do with those -- a lot of those intangible qualities of deterrence. What deterrence means in the nuclear age for us and our potential adversaries. [ Jacques Arsenault: ] So part of that is if one of the legs were knocked out by a nuclear attack there would still be other ways to deliver? [ Joe Kirschbaum: ] Correct. At a minimum that is one of the characteristics and there are others. [ Jacques Arsenault: ] So this is the public version of a classified report and we're not going to get too far into the details here, but can you give me a sense of what the Department of Defense does to assess the legs of the triad? [ Joe Kirschbaum: ] The Department of Defense over the years has conducted routine assessments of what the triad comprises, how to keep it up-to-date, and all of those considerations. After the Cold War in particular, between 1994 and 2001, they conducted several major reviews. The one we were primarily concerned with in our review was the nuclear posture review conducted in 2010. And they considered various options to maintain the U.S. nuclear forces including options where the United States might eliminate one of the legs of the triad and to see what impact they may have. [ Jacques Arsenault: ] And so generally speaking, what are the strengths of each of the three legs of the triad? [ Joe Kirschbaum: ] Some of the characteristics of that are intangible for deterrence, you know. What does it mean to deter an opponent using nuclear weapons that hopefully will never be used? So some of them will go to those intangibles but they have very tangible characterizations and manifestations. For example, the ICBM missiles, those are the most easily communicated with, the most prompt in terms of use. So that provides that stability. The bombers, the aircraft, those provide that -- some of those intangible diplomatic aspects. They can be used for signaling intent. They can be flown to locations to signal intent and once again to back up the -- one of the means for deterrence is maintain which is that we're serious. And then the sea-based leg of the triad, the submarines, are the most survivable. So that in the event that a nuclear attack was conducted first on the United States, those forces would all survive and would be immediately available to devastate an opponent which is another key aspect of effective deterrence. [ Jacques Arsenault: ] Now, in addition to looking at the triad, your report also looked at actions around nuclear force reductions. Can you tell me what steps DOD is taking here? [ Joe Kirschbaum: ] This one is fairly important because it's context for all of the looks that the department is done in terms of the makeup of the strategic triad. So in 1991, for example, about the time of the end of the Cold War, the United States had some 13,000 nuclear weapons, bombs, warheads, whatnot. As a result of some of the strategic arms treaties and reductions in 2011, we had less than 4,500. That's a severe decrease. So this is all context for what the department's considering of how to structure its nuclear forces with those reductions in mind and consideration of future reductions. For example, in 2010, the president signed the New Start Agreement with the Russian Federation which will lead to further reductions in warheads. So the department's considering what the strategic nuclear forces have to be to encompass those reductions. [ Jacques Arsenault: ] And finally, what would you say is the bottom line of this report? [ Joe Kirschbaum: ] The bottom line is that the department has conducted these reviews to look at the makeup of the strategic triad, and they've looked at it in the context that I've mentioned with what's necessary to maintain the credibility of the deterrence forces. And their conclusion really is that to retain all three legs of the triad in order to maintain that stable nuclear force structure and to support deterrence. And all of this happens in the context of the importance of the monetary aspects of it. Each one of these legs of the triad are aging rapidly. They're all intended to be deployed beyond their service lives and the Departments of Defense and Departments of Energy have reported that it's going to require upwards of $320 billion between fiscal years 2016 and 2025 to maintain these forces. 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