Why No Ballistic Missiles in Vietnam?

In last week’s Airpower class, someone wondered why conventionally armed ballistic missiles weren’t used by the United States in the Vietnam War. The answers seem obvious, but then explaining why stupid things don’t happen is easy; it’s harder to explain why some stupid things happen and others do not. I don’t recall ever seeing a proposal to use ballistic missiles against North Vietnam, and I’m curious as to why not.

Briefly, a  case for ballistic missiles use:

1. Ballistic missiles require neither pilots nor escorts, limiting the cost differential between the huge strike packages deployed against North Vietnam during the war.

2. Available missiles (primarily the Redstone, but also early Pershings) could carry conventional payloads sufficient to give some confidence in destruction of “precise” targets.  The Redstone had a CEP of 300 meters and could carry a very big warhead, making the destruction of large-but-specific North Vietnamese targets plausible.

3. Some evidence from World War II indicated that ballistic missiles had a morale effect distinct from conventional strategic bombing.  The utter inability of the target to predict or resist the strikes increased the sense of helplessness at both elite and popular levels.  To be sure, this evidence may be regarded as reasonably twitchy, but not much less so than the evidence used to justify the broader Rolling Thunder campaign.

4. The Army had plausible institutional reasons for arguing for MRBM strikes against North Vietnam, given that it controlled the missiles and the Air Force did not.

5. Escalation concerns were manageable.  Simple notification of the Soviets or Chinese immediately prior to launches, combined with a specific geographic zone of operation, probably would have been sufficient to prevent a crisis, if not very loud complaints.

6. The number of available missiles was limited (120 Redstones, 750 Pershing Is), but it was still possible to envision a Schelling-approved coercion campaign; a dozen missiles hit Hanoi to demonstrate resolve and capability, saving a sufficient number in reserve for a larger series of strikes, etc.  Recall that the purpose of Rolling Thunder wasn’t so much to grind Hanoi to dust as to convince the DRV to give up the campaign in the South.

And here are the arguments against.  When we’re evaluating these, recall that we’re talking about people who could be convinced a) that defending South Vietnam was a crucial US strategic interest, b) that the deployment of ground forces to South Vietnam represented an acceptable cost in defense of that interest, and c) that a strategic bombing campaign against North Vietnam was both an appropriate and potentially decisive policy tool.  The point isn’t to say that hitting Hanoi with ballistic missiles was stupid, but rather to determine why the people who thought all of the above things didn’t cotton to the idea of Pershing Is raining down on Ho Chi Minh’s head.

1. The politics were all wrong.  Ballistic missiles were, the V-2 notwithstanding, associated with nuclear weapons at the time.  The political atmospherics of hitting Hanoi with SRBMs seemed politically more risky that hitting it with B-52s, even though the latter had also been initially designed to deliver nuclear warheads.  Perhaps also the V-2 example was problematic because it associated the use of ballistic missiles with the Nazi regime. Finally, the recent example of the Cuban Missile Crisis (even though it involved nuclear armed missiles) would make anyone leery about deploying SRBMs to a US client state.

2. Escalation concerns were genuine, and intertwined with political concerns.  The Chinese and Russians probably wouldn’t have believed that SRBMs launched from South Vietnam were really nukes in disguise, but the stakes were extremely high.  Moreover, Moscow and Beijing could point to the deployment and use of SRBMs to paint Kennedy/Johnson as mad men, which would (for some reason) sound more compelling than a similar argument referencing nuclear capable strategic bombers.

3. The expected military benefit was simply too small, given the cost of launching and maintaining the missiles.  The Redstone could deliver a huge payload and the Pershing a respectable one, but nothing along the lines of what a B-52 (or even an A-6) could deliver in a single sortie.  Moreover, even a 300 meter CEP means that a very large warhead could hit right in the middle of a civilian area; although bombers dropped more ordnance, the individual weapons were much smaller, presumably reducing the potential for civilian damage.

4.  The plan was unworkable for technical reasons.  Redstones, for example, required an immense amount of infrastructure, and while much of this probably could be imported to South Vietnam, the cost would be prohibitive.  Moreover, some of the details don’t work out; the Redstone could carry an enormous (6000#!) payload, but its range was only 210 miles, and it was 280 miles from the closest plausible launch sites to Hanoi.  Maybe the range couldn’t be extended by reducing payload, or maybe accuracy would suffer, or maybe no “sweet spot” could be found that would deliver a payload of sufficient size to destroy targets in the Redstone’s accuracy spread.  And maybe the Pershing simply delivered a warhead (600#) too small to do sufficient damage given its CEP (400m).  The Jupiter had the distance, but had a CEP of 1500 meters, which makes it pretty much useless for delivering anything but a nuclear weapon.

5. The organizational incentives are all wrong.  The Air Force would fight against the use of ballistic missiles because they love their bombers and think that the planes can do the job.  The Army (which actually operates the SRBMs) tends not to think in such strategic terms, preferring to concentrate on the tactical and operational details of fighting the war in the South.  Any serious proposal would have pit serious USAF opposition against an Army that felt very “meh” about the whole idea.

And so I’m interested in two types of response.  First, is there any historical evidence that US military or civilian policymakers actively considered and rejected the use of ballistic missiles, and if so does that evidence give any clear indication as to what they believed the relevant objections? And second, if there is no such evidence (or even if there is; it’s irresponsible not to speculate) why was there no such active discussion; what made policymakers reject or ignore the notion without even giving it a hearing?