submariners were instructed in group tactics,
whereby “wolfpacks” of submarines, linked
by short-wave radio, converged upon a single
target. Dönitz’s reasoning was obvious: When
tackling a convoy attended by heavily armed
escorts, there was greater safety—and suc-
cess—in numbers. Furthermore, he specified
that torpedo attacks should be made from the
surface at night, not while submerged in day-
light. This change improved both the accu-
racy of torpedoes and the survival rate of
U-boats.
Dönitz placed great faith in submarines as
strategic weapons and felt they were the only
effective foil to counter the large, well-
equipped Royal Navy. Furthermore, he real-
ized that the submarine exerted it greatest ef-
fect by attacking commercial, not military,
targets. In the event of a future war with En-
gland, he advocated throwing a ring of steel
around the British Isles and starving them
into submission. Dönitz also assisted in help-
ing develop new classes of U-boats that were
faster, more heavily armed, and deeper-diving
than the leaky tubs of World War I. He aspired
to have at least 1,000 such vessels deployed
should war commence, but interservice ri-
valry made U-boat procurement a very low
priority. Consequently, when World War II
erupted in September 1939, Dönitz possessed
only 56 submarines—half of them obsolete—
to fulfill his strategy. Such scant numbers be-
lied their effectiveness, however, for Ger-
many’s submarines were well equipped and
manned by brave, capable crews.
In the first few months of the war, the U-
boat packs were amazingly successful at sink-
ing Allied merchant vessels. Their labors were
abetted by confusion within the Royal Navy,
which had forgotten the lessons of convoying
ships from World War I. Consequently, this
was the “happy time” of the submarine war;
by December 1940, U-boats accounted for 400
Allied ships weighing 2 million tons. By the
fall of 1941, Britain had very nearly been
starved out. Furthermore, among Dönitz’s
many victims was the American destroyer
USS Reuben James,which was inadvertently
sunk in a war zone. Thereafter, President
Franklin D. Roosevelt directed naval chief of
operations Adm. Ernest J. King to wage a
clandestine, undeclared war against German
submarines. This action proved a harbinger of
things to come.
German submariners enjoyed even greater
success following the declaration of war
against the United States in December 1941.
The nation was unprepared for unrestricted
submarine warfare, and within six months the
U-boats sent 585 vessels weighing 3 million
tons to the bottom. Such losses impeded
Great Britain’s ability to wage war, and for a
second time Dönitz’s strategy nearly suc-
ceeded. But as the Battle of the Atlantic
raged, new technology helped the Allies grad-
ually gain the upper hand. Unknown to
Dönitz, American and British intelligence
agencies had decoded his messages and were
alerted to the location of each wolfpack. Ex-
isting detection technology such as sonar was
also refined and enhanced, and U-boat losses
mounted. The perfection of microwave radar,
once mounted on airplanes and blimps, also
allowed U-boats to be stalked at night once
they surfaced to recharge their batteries. By
1943, German losses at sea were prohibitive,
and Allied convoys enjoyed almost unfettered
access to English ports. “The enemy knows
our secrets and we know none of his,” Dönitz
sadly conceded. He nonetheless kept a steady
stream of ships and crews flowing into the At-
lantic to delay the inevitable Allied onslaught
for as long as possible.
By January 1943, Hitler was increasingly
dissatisfied with his navy’s performance, so
he sacked Admiral Raeder and placed Dönitz
at the helm. As commander in chief, Dönitz
placed greater emphasis on the development
of new boats to counter recent Allied gains.
He had pushed this concept for years, but
Raeder, a supporter of the surface strategy, re-
fused to allocate the resources. Eventually,
the highly advanced Type XXI submarine
evolved, which was three times faster than
conventional U-boats; by using a snorkel, it
could recharge while still submerged. TheDÖNITZ, KARL