FOREIGN RELATIONS, 1934, VOLUME III



bridge and funnel. Cruiser and counter sterns appear to be about
equal in number. There are a few three islander types in the fleet,
notably the new M. B. K. boats.
  It does not require a professional eye to discern from the above
figures why such vessels are of value to the Japanese Army and Navy.
'The combination of great cargo capacity and large fuel and deep
tanks with wide cruising radius and, above all, astounding speed, make
these craft without peer for military and naval supply ships, trans-
ports or emergency tankers. Perhaps even more important would be
the value of these ships in transporting food, fuel and munitions at
express speed to a beleaguered country at war. These ships are as
much a "life line" to an island Empire as certain of the continental
"life lines" more generally associated with that term.
  There is, however, one grave strategical defect which has been
permanently built into these vessels. The greatest mineral resource
of Japan is coal. The one fuel upon which Japan might rely during
a period of extensive blockade is coal. Fast steamers can be trans-
formed from oil burners to coal burners in a week, but a motor ship
remains a motorship and can burn but one kind of fuel-oil.
  There are beyond doubt immense supplies of oil in reserve for the
account of the Japanese Navy. The recently passed Oil Control Act
further increases the potential supply by its requirement that im-
porters and refiners of petroleum must keep constantly in storage oil
to the amount of half their annual importation. In other words, in
the event of a blockade Japan would have a six months' supply of
petroleum on hand before even touching its emergency reserve. These
facts mitigate but do not remove a weakness which, in the writer's
opinion, might easily be made fatal by the successful previous loca-
tion and later destruction of oil reserves by aerial attack. Oil is stored
in tanks or subterranean reservoirs and either is vulnerable to bombing.
  The great defect of these extraordinarily swift ships is that they
can not utilize the natural fuel of Japan. Proper strategy would
indicate that the line for Japan to follow would be in the perfection
of superheated steam giving impulse to geared turbines and motivated
by pulverized or colloidal coal. Two fine Japanese liners are fitted
for pulverized coal and utilize exhaust turbines, but no notice was
evidently taken of Nagoya Maru and Johore Maru, for the Japanese
vards have gone over practically entirely to the building of diesel
motors. Irrespective of the question of efficiency of motor propulsion,
the strategical weakness remains and should be remembered.
  Another but far less important drawback to the strategical value
of these new vessels is that most of them are to be placed in the trade
to the Atlantic Coast of the United States. A sudden emergency in
a certain quarter would cut off half these vessels on the eastern side



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