* * * *
This review is based
on a complimentary copy sent to me by the publishers after I had
bought my own copy from them.
Secret Alliances is
a comprehensive history of political, military and intelligence
relations between Britain and Norway during and just after WW2. There
were several different organisations on both sides, each with
different priorities, largely according to what their mission was.
The author illustrates the interplay of these differing priorities
with a large number of incidents, some already famous, some not, but
in nearly all cases with new material from his research and that of
other scholars. Since I had read many different books about various
different incidents in Norway and the circumstances in which they
occurred over more than forty years (I have been interested in the
issue since my teens), the experience of reading this book was one of
bubbles of recognition in a stream of information that was mostly new
to me.
For example, what
some authors have described as “failed” attacks on the German
battleship Tirpitz often did significant damage and would have
prevented her being capable of taking offensive action for months at
a time. A major contribution of Norwegian agents reporting both to
their own government and to Britain’s SIS, was detailed information
about how much damage had been done, how repairs were going and
therefore how urgently further attacks were needed. Great sacrifices
were made to keep the Tirpitz out action; the evidence in this book
suggests that without Norwegian agents on the ground and an
organisation that allowed them to report intelligence swiftly, more
attacks and even greater sacrifices would have been necessary. The
“X-craft” attack was much more effective than I’d been led to
believe by previous publications, TV documentaries and one war-movie,
which tend towards the “heroic failure” narrative. The Tirpitz
was heavily damaged and unseaworthy for some time -and SIS and NID
knew this. Similarly, during the attack by Fleet Air Arm Barracuda
bombers (only able to carry one 1,600lb AP bomb each), although none
of the bombs penetrated the armour on the battleship’s citadel,
hits on parts of ship outside the citadel started fires which damaged
sea-pipes and caused flooding and a list to starboard forcing the
crew to swing the main guns out to port to balance the ship. A clear
and obvious sign that she wasn’t about to take to the high seas in
a hurry. Reports on the damage done by this raid started to arrive on
the same day as the attack, from the same agent who had risked his
life to give regular weather reports in the lead-up to the attack to
ensure it took place in ideal conditions. (This is another factor
which previous books haven’t made much of, but it must have crucial
for operations over Norway.)
There is new
material on how the German forces tracked agents down by their radio
transmissions, and it appears that insufficient attention was paid
by SIS to German direction-finding techniques. Having also read some
histories of what the British “Y service” did to track down
transmissions by German agents in the British Isles, and indeed by
Japanese and German army and naval units over much of the world, it
is staggering that SIS could have remained so ignorant, unless there
was a complete firewall between them and the Y service! (The Y
service had an index systematically describing the “static”
noises made by individual enemy radio sets, enabling them to locate
certain enemy units on the move even if it was impossible to read the
cyphers (or Japanese vocabulary) being used. I don’t know if the
Germans had the same idea: it was tracing the set, not the “hand”
of the operator, which is a separate issue.)
The political
information is interesting, too: it shows that Norwegian ministers
faced problems and dilemmas over neutrality and the potential Soviet
threat that could only be resolved by creating the NATO alliance
which allows countries like Norway to enjoy security without
sacrificing sovereignty and principles.
Criticism:
With so much light
being shed by this book, it is a pity that where the issue of heavy
water production in Norway for the Germans is concerned, the author
manages to add to the confusion and lack of popular understanding
about what, exactly, the heavy water was for and why this was so
important. Every author on this subject seems to find it necessary to
confuse things and I, having managed to get a Grade A O’level in
Physics with Chemistry back in the day, despair of them all. What
follows goes a bit beyond being a review and strays into trying to
set things straight, for which no apology is going to be made.
On page 252 it is
stated that heavy water was the moderator used to separate (fissile)
U-235 from (fissionable) U-238. This muddles together two separate
processes applying to completely different routes to making an atom
bomb. A moderator, such as heavy water or graphite, is used to slow
down neutrons in a reactor, increasing the likelihood of a collision
with nuclei in the fuel isotope, promoting a reaction and the release
of energy and the creation of some other isotope, which may be what
the reactor is designed to produce. The two pertinent examples would
be to convert the U-238 in natural or low-enriched uranium to Pu-239,
which would be desired for weapons, and Pu-240, which in large
concentrations prevents an effective bomb being made -and the
conversion of Th-232 (Thorium) into U-233, which can be used to make
a bomb in nearly the same way as Pu-239, a similar complication being
the creation of U-232 which not only stops the bomb working properly
in high concentrations: it makes the material more dangerous to
handle than weapons-grade Plutonium. “Separating U-235” refers to
the production, from natural uranium of low or highly-enriched
uranium with a higher content of fissile U-235 as well as “depleted”
uranium which is nearly all U-238, which is not fissile but is
fissionable if struck by neutrons with a high enough energy. These
may come from fusion reactions or (to a lesser degree) from the
fission of Pu-239.
There are several
methods by which natural uranium can be enriched: at least two
different methods were used by the Allies during WW2: if the Germans
did the same then I am unfamiliar with the evidence.
In his conclusions
towards the end of the book, the author suggests that there were two
possible routes to an atom bomb: the Germans chose the wrong one and
the Allies chose the right one. This is untrue in several ways at
once, and cannot be allowed to go unchallenged:
There were three
routes to an atom bomb known at the time: enrichment of U-235,
production of Pu-239 in a reactor and production of U-233 in a
reactor or, in the American case, the same reactors used to produce
Pu-239. The Allies did not “choose the right one”: they pursued
all three, with less effort being applied to the U-233 route
as long as the Pu-239 route seemed to be working for them. Both U-235
and Pu-239 bombs were produced and used by the Americans in WW2, the
two bombs having different operating principles, although a U-235
bomb could have been made either way. The Americans may have produced
enough U-233 for a bomb by 1946, although they did not detonate a
bomb containing U-233 until 1955. Once a Pu-239 implosion bomb had
been seen to work, over Nagasaki, a U-233 implosion bomb could be
assumed to work. The 1955 test was of a composite core, containing
both Pu-239 and U-233 about which fewer assumptions could be made,
hence the test.
The Germans did not
“choose the wrong method”; they tried to pursue Pu-239 and U-233
bombs, both of which have since been made to work. (The USSR
detonated an H-bomb with U-233 in its primary device and India
detonated a small tactical device in 1998 using just U-233.) Neither
German programme got very far, partly due to the lack of heavy water and
perhaps a failure to realise that graphite could be used instead
(some German scientists knew quite well that it could be). The German
efforts to use Thorium and U-233 are habitually derided by those
authors who notice them at all, but there is a great deal of
practical sense in doing this:
Although it is
possible to make either Pu-239 or U-233 in the same reactor -and the
Americans did just that- in neither case does weapons-grade material
come out of the reactor. What you get is either a large mass of
uranium containing and small mass of Pu-239, Pu-240 and other
by-products, or a large mass of thorium containing a small mass of
U-233, U-232 and other by-products. What you have to do next is some
sort of chemical refining to produce pure plutonium
(it’s not possible to separate Pu-239 from Pu-240 once they are
mixed, by any known method) or chemically extract U-233 and the
similarly unavoidable U-232 from the thorium.
U-235 can be
separated from U-238 only because there’s a slightly bigger
difference in the atomic weight of the two isotopes than is the case
with U-233 and U232. And it is a time and energy-consuming task.
Not only did the
Germans lack American industrial capacity in absolute terms, the
industrial capacity they had, relevant to processing their reactor
products, basically consisted of the industry, established since
1891, which separated industrially-useful thorium from silver. So,
the thorium/U-233 route would have seemed like safer ground to German
officials attempted to plan for the solution of novel problems. What the
Germans did, actually made sense given the knowledge, resources and
worker skills that they had.
The failure of
the German atomic bomb projects was not a foregone conclusion and
the risk of their success was not negligible.
PS: If you have a
fine German silver teapot dating from before the time when the
Germans learned how to separate the thorium in their silver ore from
their silver, it’s probably best not to use it for actual tea that
you’re planning to drink.
Secret Alliances is
published by Biteback Publishing on the 28th of April
2021.