ASK DR. SCHUND
                    (C)1991 Alan M. Schwartz

Dr.  Schund, what is the thermonuclear sostenuto pedal?

Cheap pianos have a "loud" pedal and a "soft" pedal.  Quality 
pianos have a third pedal placed squarely between these two - the 
subtle, the miraculous "sostenuto" pedal.  It selectively quiets 
the G-clef lines while sustaining the bass harmony, allowing 
your right hand to cleanly execute hyperkinetic gymnastics through 
the melody while your left hand enjoys the California lifestyle.  
Imagine Dr. Schund's surprise upon learning that quality 
thermonuclear warheads work in much the same manner.

The common perception of a ten megaton H-bomb detonating at 
30,000 feet is that of the sudden creation of a glowing crater a 
few hundred feet deep and a couple of miles wide, with ancillary 
nuisances radiating out to the horizon.  Terran governments have 
accumulated near 100,000 devices.  One imagines they foresee a 
day when all real estate is a buyer's market.  Consider Congress, 
whose members have exempted themselves by law (so it's all right) 
from Social Security's endless hunger gnawing at their paychecks.  
Might we suspect that if World War III intrudes, certain 
arrangements have been made to protect those who will run the 
show, as opposed to those who will only run?

Thermonuclear gadgets are implosion devices, layered like onions.  
A spherical shell of initiators and explosive lenses creates a 
smoothly collapsing detonation wave to trigger a spherical shell 
of high explosive.  The boosted and still collapsing and 
concentrating shock wave impacts a shell of natural uranium with 
a density more than 19 times that of water, the implosion tamper, 
and SQUEEZES.  A gap maintained by low density plastic foam is 
next encountered, allowing the densely shrinking hypersonic hell 
to further accelerate before impacting the plutonium core.  
Compressed to as much as 200 times the density of water in a 
fraction of a microsecond, critical mass is exceeded, birthing a 
peewee atomic explosion, much of whose ten kilotons of energy is 
radiated as x-rays, closely followed by a hundred kilograms of 
expanding plasma hotter and denser than the core of the sun, and 
wanting OUT!  The matter is less interesting than the energy.

The x-rays are faster, traveling at lightspeed.  They flow into 
the body of the bomb by bouncing off its laminated inner surface, 
sculpted with sub-micron precision with alternating curved layers 
of dense and light elements to form an evanescent x-ray mirror.  
The remainder of the bomb is pumped down to a hard vacuum and 
filled with more low density open-cell foam.  At its center is a 
long cylinder, also layered like an onion.  A central plutonium 
core is wrapped with ceramic lithium-6 deuteride and tritide, 
surrounded by another foam gap, surmounted by a thick and dense 
implosion tamper skin.  The x-rays flood the length of the bomb 
and the foam fill flashes into hyper-pressured plasma which, 
we've been here before, axi-symmetrically embraces the central 
cylinder.  Implosion tamper becomes a dense hypersonic material 
shock wave, accelerates across the gap, implodes the ceramic, 
implodes the plutonium, and triggers another fission blast.  With 
hell coming in and hell pushing out and a deluge of neutrons hot 
to party, lithium drinks a neutron and fissions to deuterium and 
tritium, adding to the heavy hydrogen inventory undergoing fusion 
for the main event - thermonuclear armageddon.  If the bomb 
casing is uranium, and it is, outgoing neutrons fission it too, 
adding insult to injury.  We will call this the "loud" pedal.

In the late 1950's the United States and Russia discovered how 
to make a "dial-a-bomb." By altering aspects of internal bomb 
geometry before launch, a single warhead could be assigned one of 
many yields.  We entered the era of the surgical strike, wherein 
a small cluster of Congressional districts rather than a complete 
state could be obliterated.  We will call this the "soft" pedal.

What would be the point of vaporizing Washington, Moscow, or a 
covertly CIA-funded 7-11 (it is the one in Pacoima that never 
gets robbed) if world leaders ruined each other's wine cellars?  
What of their remaining years on post-holocaust Earth?  The 
superlative microminiaturization of complex circuitry in the 
1980's, and the advent of supercomputers that could almost 
literally follow all the atoms of a bomb as its detonation was 
modeled, made it possible to deliver a thermonuclear warhead 
within feet of its desired destination, and to lower the symmetry 
of its implosion processes, creating holes in its blast wave.  
The governments of civilized nations of planet Earth pledged to 
play the game fairly, resigning themselves to the necessity of 
flash vaporizing Barbara Bush or Raisa Gorbachev, but promising 
to spare mistresses and drug caches as long as they were 
registered in the shared international Doomsday data base.  We 
will call this the "sostenuto" pedal.

Along comes Saddam Hussein with his home-made Iraqi A-bombs, and 
not a sostenuto pedal in sight.  Approved thermonuclear warheads 
threatening officially allocated populations were but a memory.  
Suddenly mistresses and drug caches were again vulnerable to a 
madman's depredations!  Something had to be done, and neither 
Moscow nor Washington peeped a dissenting murmur as the harsh 
tones were muted.