Is Speed the New Stealth?

Recently at Angle of Attack, a journal of Air Power Strategy, feature author Chris Buckley identified the underlying assumptions of why the nuclear-armed cruise missile was and remains necessary. While Buckley claims this new cruise missile must be nuclear-armed, there is a pathway to a new cruise missile that will achieve all of the strategic demands without a nuclear warhead. Buckley’s historical analysis lays the pathway to future decisions. Many organizations put forth compelling arguments to the redundancy of the nuclear-armed cruise missile. So let’s assume that both are correct; the US needs a new cruise missile, but it should not be nuclear-armed. How does the Pentagon achieve this? If the mixed bomber fleet is something we need and the air-breathing leg of the triad remains necessary, how is that possible without a nuclear-armed cruise missile?

Hypersonic long range standoff (LRSO)  missile is the answer.

The Pentagon is on the wrong track with the current LRSO. As Buckley states, the ALCM was used as a hedge against unknown advances in SAM technology. If that remains the case, then the LRSO must be hypersonic.

In the world we lived in before the advent of cruise missiles, the only viable method of destroying targets protected by advanced air defenses was the ICBM or the penetrating bomber. The Cruise Missile, in essence, replaced the penetrating bomber in that equation. It was the cruise missile that did the penetration. The determinant factor in this case is detection. For aircraft and cruise missiles, the detection method is radar, which the US attempted to defeat by making cruise missiles small and aircraft stealth, and then making cruise missiles stealth as well. If one can delay the detection long enough, there isn’t enough time to engage. The penetrating bomber was after the same thing, reduced detection to limit engagement times. The B-1 went fast and low, reducing detection ranges. The B-2 is stealth, reducing detection ranges. As the radars got better, we made better stealth. The goal always remained the same. Reduce the time allotted to engage.

Shift gears to the ICBM, a weapons system that is practically indefensible. How does it do that? Detection is achieved through satellites at launch. The adversary can see the ICBM coming from another hemisphere. While the detection timeline is large, the engagement timeline is so small that it cannot be effectively engaged. The high confidence in ICBMs is not because it can avoid detection, and not because it is nuclear-armed. It is because it’s really fast.  ICBMs travel at hypersonic speeds achieving 5-7 kilometers per second terminal speeds, equating to Mach 14 to Mach 20.  If a cruise missile can achieve that speed it would be indefensible, and would also not require a nuclear warhead.

A hypersonic LRSO is the solution to re-creating the capability gap the US enjoyed with early cruise missiles against early SAM systems. Hypersonic LRSOs could attack the newest S‑300 systems directly, with impunity.  A hypersonic LRSO will boost to 200,000 feet and cruise towards the target from 1,000 miles away at Mach 6.  Close in, the missile will dive over from the upper stratosphere and slam into its target from directly overhead at five kilometers per second.  Air defenses will not be able to engage this missile with anything resembling consistency, whether the systems detect the missiles or not.^[1]  This hypersonic LRSO re-assert the concepts of Global Strike in the face of A2/AD proliferation.  This is not a new idea; it is just a faster old idea.

Speed is the new stealth.

Specifically developing the hypersonic LRSO without nuclear weapons is an opportunity for the US to change the conversation regarding nuclear-arms proliferation without losing any capability.  The US has been on a decade-long journey to increase its capability to produce strategic effects without the use of nuclear weapons, and hypersonic missiles is a watershed moment in that journey.  It has made a determined effort to reduce reliance on nuclear weapons in deterrence, extended deterrence, and in non-nuclear options even after nuclear use has occurred.  Having non-nuclear strategic offensive capabilities offers many advantages over any reliance on nuclear weapons.

(1) Strategic deterrence is actually enhanced since the threat of using non-nuclear weapons is generally seen as more credible than a nuclear threat.

(2) A non-nuclear strategic strike may be a better method of restoring deterrence in the event deterrence fails.  If an adversary uses nuclear weapons, the question becomes, “how does one restore deterrence?”  The international community is in general agreement that nuclear deterrence is established when the user feels that the penalty for nuclear use is exceedingly high.  Responding with nuclear weapons would certainly serve this purpose but at the same time undermines the position of not using nuclear weapons.  In other words, a nuclear response may be counterproductive in re-establishing nuclear deterrence.

(3) Non-nuclear strategic offensive capabilities have introduced an intermediate level on the escalation ladder.  For years, the United States has been searching for a level of warfare between conventional theater war and general nuclear war.  A non-nuclear strategic strike provides flexibility to act as a firebreak to nuclear escalation.[2]

Granted, a non-nuclear strategic strike is not as easy to achieve as you have been led to believe. Take, for example, an airfield as a target. In today’s paradigm, a single ALCM with a nuclear warhead can destroy or degrade that airfield to the point it is no longer usable. Could a non-nuclear, hypersonic LRSO achieve the same thing? Perhaps, but it would probably take more than one. So while the efficiency of such a strike would decrease in the non-nuclear case, the advantages of operating in a non-nuclear world are worth the risk. Can the entirety of our nuclear arsenal be replaced with non-nuclear weapons? Unlikely.  But can the air-breathing portion be replaced? Much more likely.

A non-nuclear, hypersonic LRSO would help shed the last bastion of Cold War ideology and fully change the nuclear triad to the strategic triad, as defined in the 2001 Nuclear Posture Review.  The new triad replaced the Bombers-Submarines-Missiles Triad with Offense-Defense-Infrastructure.[3] A non-nuclear, hypersonic LRSO working as a strategic-strike platform serves to promote strategic stability and works to reduce US reliance on nuclear weapons while allowing it to remain postured to deal with the entire spectrum of conflict up to and including nuclear war, at the same time promoting counter-proliferation policies.

With a hypersonic LRSO, the Pentagon can achieve all of their needs without the need for nuclear warheads on cruise missiles. Strategic effects will be retained and nuclear arms will be reduced. The hypersonic LRSO is a win-win.

The USAF should field a non-nuclear, hypersonic LRSO with the intention of replacing the AGM‑86B ALCM and AGM‑86C CALCM.  The hypersonic LRSO removes the vulnerability of the ALCM and CALCM against modern air defenses while integrating into existing paradigms concerning Global Strike doctrine.  As hypersonic LRSOs replace ALCMs in the strategic nuclear mindset, ALCMs should be converted to CALCMs.  While the ALCM and CALCM remain vulnerable to modern air defenses, those defenses are not omnipresent.  The CALCM is still valuable as a long-range conventional standoff strike weapon, and there are many regions and theaters where CALCM use is both warranted and desired by Combatant Commanders.  It is in this way that the USAF should divest itself of ALCM and CALCM, through attrition.  Similarly, the US Navy should pursue hypersonic replacements for the Tomahawk and Harpoon, retiring those systems also through attrition or sale.

 

[1] “Hypersonic Missiles: Speed is the New Stealth,” The Economist, June 1, 2013.  http://www.economist.com/news/technology-quarterly/21578522-hypersonic-weapons-building-vehicles-fly-five-times-speed-sound

[2] Andrew F. Krepinevich and Robert C. Martinage, “Transformation of Strategic-Strike Operations,” Center for Strategic and Budgetary Assessments, March 2001, ii-iii.

[3] Donald Rumsfeld, “2001 Nuclear Posture Review,” Department of Defense, 2001.