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MH-15: Pacific & Atlantic Theaters

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Pacific & Atlantic Wars (1941-42) Strategic Overview

• When US & USSR entered WWII=> – The war became global in scale

• Key challenge for US participation in war: – Mobilize & deploy its industrial might to Europe & the Pacific– To accomplish deployment of its mobilized force =>

• US must protect LOC to Europe• Problem & major challenge to protecting LOC?

• By 1942: US able to halt Japan’s Pacific expansion –how?– US able to mobilize substantial resources;– fight and hold their own in massive battles w/Japanese– also USN addressed submarine threat by end of 1942– Then the US turned the corner => initiated power projection

German ?____ threat

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Initial Limitations• NTL=> at start, Allied attack on Germany limited to

primarily what? – Strategic Air Strikes, while…– Maintaining defensive posture in the Pacific

• Allies’ primary grand military strategy? – Germany first!

• Any problem with Germany first following December 7th ?– US public opinion focused anger toward who?

• Impact: Public Opinion forced some shift in additional assets to Pacific theater:– Divided up between what key Pacific

area commanders? General ?__________ & Admiral ?_______

?________

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Naval War- Two key Theaters of War • Atlantic:

– German SS threat: troop transport/supply LOC

– US employed convoy system and anti-SS warfare

• Pacific: – Large surface engagements

(primarily with CV- Air)– Pacific’s geography

dictates different strategy– Primary Operational

strategy: island hopping: – Land/air and sea forces

required to accomplish– Gradually more & more

assets shifted to Pacific

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Pacific Theater- to 1941 • War in the Pacific - its origins? => scarce resources!• Pacific War’s Origins:

– Japan’s lack of strategic natural resources => (oil & minerals)• Impact: major strain on national economy;• Further compounded by global $$$ depression of the 1930s• All taking place during growing radical

nationalists sentiment• Japan’s solution to its problems:

– Expansion beyond Japan seemed an obvious solution =>

• This attitude was shaped by growing military influence

• Military controlled by extreme nationalists– Most likely target for Japan’s expansion?

• NE ?__________ => easy target for expansion => Manchuria (Map)– Strategic Motive? (Manchuria is rich in coal and iron ore)– 9/16/1931: Junior Officers of Army blow up Rail line near Mukden to

fabricate pretext for invasion & subsequent establishment of “Manchukuo”

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Japan On the Move• Japanese Army conducted aggressive actions toward

China:– 1937: Fabricate Marco-Polo bridge incident

• Pretext for extensive intervention into China

– Japan thus conducts undeclared war on China:• Occupies & controls major Chinese ports & cities

• Japanese commit atrocities- especially at Nanking

• Countryside remains contested – by who?

• Nationalists & but especially ?_____________________ forces

• Aug 1939: USSR (LTG Zhukov) defeats Japanese in 3 days at Nomonhan:– Japan learns a serious lesson

– Avoid direct combat with Soviets in future• Germany failed to learn from Japan’s experience

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US Defense Posture• US views Japanese expansion in Asia with growing alarm

– American Government issues sharp protest:• Asserts Japanese actions in China unacceptable:• What action does US initially take as a result?• No direct US assistance to China against Japan (rhetoric only)

• US capability to back up its protest against Japan:– How prepared is US to defend interests in PACOM?

• US spends token sum on defense in Asian (PI) region:– American Pacific island interests get little funding

• Spring 1940=> Japan incorporates SE Asia:– Now to be part of Japan’s New Order in Pacific

• Nov’40: Japan deploys troops to Indo-China– July ‘41: Japan seizes South Indo-China =>

• Specifically in British & Dutch colonies in SE Asia -why?• Taken as ?_________________ position for future advances

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Strategic Implications• Implications for US interests

in Philippine Islands?– America finally realizes

Japan’s potential threat-PI!

• US Response: embargo oil & other exports to Japan:– Japan’s economy feels the pain – reaction?

• Growing ?____________ sentiment toward US• Japan now convinced something must be done;

• Nov 41: Gen ?_____ Hideki – (New nationalist Premier) talks

tough & aggressively– Calls for removal of British & US influence

from Far East/Pacific

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US Strategy & contingency Plans • Early US: “color plans”=> mainly offensive operation

– What was the name of the Plan for dealing with Japan?

• Plan ?_______________: – US Naval strike thru Pacific=>Japan

– Tactics: Big gun ships=> surface battle fleet engagements

– Aimed at offensive ops to defeat Japanese Navy

• Plan modification: the “Rainbow series:” – Evolved as early planning process continued

– Plans updated (late 1930s)=> for Japan:=> Rainbow ?____:

– Biggest change?• Involved shift from ?__________ to ?____________ in Pacific

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US Strategic Priorities• US (coordinating w/Brits) re-prioritize Theaters of Ops:

– Germany/Italy considered US 1st priority• Based on Hitler’s aggressive foreign policies ambitions of 1930s

– Backed by FDR (Germany on the march since 1939)

– Became established Fact in May 1940 with invasion of France:

– With fall of France => Britain now stood alone against Hitler

• Key practical reason for shift: – US simply unprepared for war at that time in history

– Full readiness will take until 1943 to fully mobilize US industry

– Complex logistic support system required for this war

– Result: => priorities for war had to be re-adjusted

• Problem: Rainbow 5 had a flawed planning assumption:– What was this flawed assumption in US planning?*

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Flawed US planning assumption • Timing!

– US planning assumption for Pacific:

– No war in Pacific until Spring of 1942!

• Plan assumed time to build up defenses in Pacific– Particularly where in western Pacific?

– The ?______________ Islands

• US planned to conduct operations from Manila as key base of ops:– US expands number of

heavy bombers & bases in PI

– Use as deterrent or capability if required against Japan

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Japan’s Timeline • Unfortunately for US planners, Japan had own timeline• But… Japan also has its own limitations:

– Its Army was extremely provincial & short sighted– Currently Japanese Army was tied down in Manchuria

• Japanese Navy had a broader strategic perspective => – For decades planned & exercised contingencies against US

• Japanese peacetime Navy superior to US in most respects:– Furthermore => Japan’s pilots were unmatched in night flight ops– Long lance torpedo weapon system was the best in world– Japan’s CV capability was fully equal to US:

• Though apparently not recognized by the US Navy at the time

• Japan’s Grand Strategy & War Plans during late 1941?*

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Japan’s Grand Strategy & War Plans (late 1941) • Strategic overview of Japan’s Strategy

& War Plans:– Japan’s Concept of Operations:

• Attack Malaya & the Philippines simultaneously

• Capture Dutch west Indies • Conduct major offensive into

Burma• Capture Wake & Guam

– (Cut US LOC to WESPAC)

• Then establish defensive perimeter about captured area: – Invite USN to attack into the

Western Pacific – Conduct SS & CV air attacks

followed by =>– Main Battle Fleet showdown on

Japan’s terms

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Operational Strategy • As modified by Admiral Yamamoto:

– 1. Initiate surprise attack on US PACFLT at Pearl Harbor:

– 2. Seize all available natural resources in Pacific– 3. Retire to defensive perimeter

behind island barriers– 4. Await US to sue for peace

• What warnings, if any, did the US have of Japan’s plans?*– Why was the US taken by both

strategic and tactical surprise?*

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Warnings & Indications • US had Intel on Japanese maneuverings early on:

– SIGINT indications & MAGIC decrypted PURPLE (Japanese diplomatic message traffic)

– So what was the problem?

• “Connecting the ?_________:” – Unable to put all together in time at

the operational & tactical level:– Also selective perception of US military leadership:

• Prevailing attitude: Japanese military inferior to US– (With racist overtones of the period)

• Warning to Pacific Fleet finally given – Via US mail! (Unable to send info by HF radio)– By that time it was too late – 0740 on Sunday morning

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Dec 7, 1941: Air Raid Peal Harbor • Pacific Naval Balance:

– Japanese Navy vs. Allies

• Focus: Hawaiian Is (Ohau)– Pearl Harbor & Hickam Field– US Pacific Fleet: Battle ship row

– NAS Ford Island– US Army & Army Air Corps:

Hickam Field

• Execution: 0740 & 0840– 2 waves of Torpedo,

bomber, & fighter aircraft strike USN & Air targets

• Major targets: Navy’s BBs & CVs; and Aircraft at Hickam AirField– Japanese gain complete

tactical surprise over unprepared US Army & Pacific Fleet

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The Aftermath

• Result of surprise attack:– USN Battleship Fleet sitting ducks at Ford Island

• Sunk or heavily damaged

– USA Air corps destroyed- most A/C parked wing tip to wing tip at Hickam

• Tactical disaster & major operational set back for USN, but…– Political, strategic & $$$ catastrophe for Japan

– Adm Kimmel & Gen Short unjustly made scapegoats

• Japan’s next major target was the PI

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Philippine Invasion• Order of Battle:

– Japanese Army: 14th Army with 2 Infantry Divisions & Fleet support

– American & Philippine forces:• 30K US with 1 USMC Regiment• 35 B-17s & 100+ P-40s• 3 USN cruisers, 13 DDs, & 6 TBs, 29 SS• 10 PI Divisions (110K)

• General Douglas MacArthur tried to defend too much:– Forward defense proved a critical

tactical error as troops pulled back• Forced to abandon arty, ammo, rations

– Major negative supply impact with time on retreating defenders

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Bataan & Corregidor • Macarthur’s forward defense strategy on the

beaches:– Plan Orange activated & Manila declared open city– Subsequent tactical impact – logistic shortfalls

• Troops forced to abandon ammo/supplies during 2 week fighting withdrawal to Bataan Peninsula

• Troops withdraw to defense phase lines on Bataan

• Japanese Army amphibious invasion with reinforcements gradually overwhelm defenders

• US strategic decision not to reinforce- why?– US Strategic priority?

• Results:– Tactical & operational victory for Japan;– Strategic & operational set back for US;– Substantial casualties: 16K KIA with 84K taken POW– Many are killed during Batan death March– MacArthur ordered to escape via USN PB to Australia

• To “return” another day – awarded MOH for evacuation

?______________ First!

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Meanwhile… The Raid• Pressure on USG to respond to Pearl Harbor disaster mounts

– FDR demands immediate results- Joint Chiefs under great pressure

– Submarine (SS) Commander develops unique & highly risky plan

• Order of Battle:– Halsey, Hornet, & Doolittle’s B-25 squadron versus:– Japan’s air defense & early warning system (to include trawlers)

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Doolittle’s Raid (April 1942)

• Concept of Operations:– USS Hornet to deploy 500 miles off Japan’s home islands– B-25s then launch from USS Hornet & head for Tokyo

• Then B-25s to conduct bomb run “30 seconds over Tokyo” – Target: Bomb key industrial infrastructure – B-25s then continue on to China & land & recover w/aid of GWs

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Execution, Results, & Significance

• Friction:– Japanese trawlers spot Hornet Task Force 750 miles from Japan

– Halsey forced to launch Doolittle earlier than desired – impact on B-25s?

• Run out of ?__________ and forced to ?______________________

• Results: Tactical versus Operational & Strategic outcome:– Tactical: Raid does little physical damage to Japan’s industry

– Strategic & political impact & significance?• Japanese military acutely embarrassed & US morale soars

– Move up prep & attack for where?*

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Battle of Midway- Lead-up (Spring 1942)

• Japan established defensive perimeter IAW their strategy:– Employs Japanese Fleet in active defense

– Then plans for two major operations:• New Guinea (against Australian forces)

• Midway Island (1300 miles NW of Hawaii)

• Operational Purpose:– Extend Japan’s defensive perimeter further East

– Invade & capture Port Moresby (New Guinea)

• Friction & problems:– Magic decrypts alert US of Japanese plans

– Admiral Nimitz prepares USN & USMC to meet attack

– Reinforces Midway Base with troops & aircraft

– Deploys RADM Fletcher w/2 Carriers (CVs) to meet imminent threat off the Solomon Islands*

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Battle of Coral Sea – (4-8 May, 1942) • USS Lexington & Yorktown

deploy to SW Pacific:– Off Eastern tip of New Guinea

– CV aircraft engage – totally out of sight of all ships involved

• Battle damage: – Japan: Shoho sunk, Shokaku

damaged, A/C & crews destroyed

– US: USS Lexington heavily damaged- later sunk by USN DD

– Yorktown damaged => repairable (48 hours emergency repairs at Pearl)

• Operational Results:– Prevents attack on Port Moresby

– Japan’s expansion interrupted

– 2 large CVs unavailable for Midway

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Battle of Midway (June 1942)- The Plan • Japan’s Plan very complex:

– Involved diversion of US Fleet toward North Pacific

– Air assault & amphibious invasion of Midway island

• Japanese Diversion plan:– 2 Lt CVs to attack US

garrisons at Attu & Kiska– 4 BB screen real intent to south– SS advance force provide

screen & early warning to East

• Invasion plan:– Main CV air strike on Midway– Yamamoto then lies in ambush

when US Fleet intervenes– 3rd Fleet to protect invasion

force from SW of Midway

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Friction & US Preparations

• Magic – USN Intel had broken Navy Op code (JN-25):– Nimitz knows attack imminent (but not sure where)

• How able to determine where Japan would strike?– N2 has series of “housekeeping” messages (complaints) sent

– N2 ruse: broken ?_______ ________ plant reported at Midway• Transmitted in the clear

– Japanese Intel encrypts & reports same info to Japanese HQ• Reveals their code for Midway by linking it with broken distillery at “AF”

• USN response & Nimitz’s preparations:– Nimitz prep: re-enforces Midway w/Air & Land forces

– Deploys Yorktown, Hornet, Enterprise to intercept Japanese• Rendezvous 350 miles NW of Midway at Point Luck• USN CV Target: Japan’s main CV force

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Battle of Midway (4 June 1942)- Execution

• TF-16 (Spruance) & TF-17 (Fletcher) combine & preposition to NE of Midway – Ahead of advance SS patrol

– US virtually ignores diversionary attack on Aleutians

– TF-17 launches recon A/C in search of Japanese CVs

• ADM Nagumo launches 72 bombers with 35 fighter (Zero) escorts against Midway– 07:10 Midway torpedo & Marauder

bombers attack Nagumo’s ships

– Keeps second strike on stand by in anticipation of US Naval attack

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Battle of Midway (4 June 1942)- Friction• Friction: bad luck hinder

Japanese from onset:– Timing favors US– Japanese Bombers rigged

with fragmentation bombs in prep for second strike on Midway

• Japanese search aircraft spot ships of US Task Forces about same time US A/C spot Japanese CVs:– TF-17 (Fletcher) directs TF-16

(Spruance) to attack while Fletcher recovers his recon aircraft

– Nagumo orders change out to armor piecing bombs to deal with US ships

– Flight crews don’t have time to secure frag bombs from flight deck

• Sacrifice of Devastators brings Japanese CV CAP Zeros to deck– Low & out of position as LCDR

McClusky’s dive bombers arrive overhead & commence attack

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Battle of Midway- “Scratch 3 flattops” • Timing of McClusky’s dive bombers

catches Nagumo’s CVs at most vulnerable, with CAP on the “deck”– McClusky’s Dauntless SBD-3s dive from

20K’ “like a silver waterfall” – Sink all three CVs: Akagi, Kaga, Soryu– US loses Yorktown by Hiryu

• (which is later sunk)

• Unique tactics employed?– All surface engagement during Battle

conducted how?– Completely by CV aircraft- no ships

directly engaged – Implication for future of BBs?

• ?___________________

• Spruance suspends night ops & decides not to engage further (criticized later)

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Operational Results & Strategic Significance• Battle of Midway impact & significance?

– Two key questions:– Operational & tactical success? (why & for whom?)– Battle of Midway strategic impact & significance?

• Operational & tactical success:– 1. CV air sunk 4 Japanese CVs (Type of success: ?__________ )– 2. Threat to Midway eliminated (?_______________ success)– 3. Destroyed most of Japanese experience & veteran air crews

(Tactical with operational implications?)• Impact on trained experienced crews ?______ _______________

• Strategic impact:– Initiative in Pacific shifts to ?___________ & never shifts back– Plans for a counter-offensive soon generate competition for

scarce Pacific resources

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US Counter-offensive in Pacific • Nimitz & MacArthur:

– Conflicting agenda of two Theatre CINCs (Central & SW Pacific)

– Competition for scarce resources:

– Army vs. Navy dispute results in JCS imposed compromise

– “Complementary” Dual Strategies questioned by Allies (esp. British)

• MacArthur’s proposed Operation against Rabaul (NE New Britain)– JCS again imposes plan modification

– 3 phased Operational approach:

– 1. Capture Guadalcanal & Tulagi

– 2. Advance along NE Coast of New Guinea

– 3. Assault Rabual if practical

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Battle of Salvo Island• Poor beginning: (Map)

– USN lack of coordination in offload of USMC & equipment

– Fletcher’s haste to depart w/CVs results in Abandonment of USMC on Guadalcanal

– Marines left w/o adequate Naval protection

• Japanese Navy strikes through “slot” near Salvo Island & attacks USN – Complete surprise &

humiliating defeat for USN

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War in the Atlantic • First Battles at Sea: Germany

vs. Britain in surface action:– No contest => back to drawing

board for Germany

– Navy retreats to safety of German ports

• Adjusted Strategy: U-Boats & surface ships as raiders;– Adm Donitz’s centralized C3

– Impressive early wolf pack success (“The happy times”)

• Effective tactics & SS Wolfpack employment:– Tactics: spot=> signal to HQ=>

converge & attack allied ships

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Allied Response• Convoy system protection had

mixed results– US learned the hard

way about convoys • Finally adopted after

serious losses to Subs

• Still Allies suffered losses but also inflicts them

• Allies finally able to effectively counter German SS threat- using Ultra & HF/DF:– Ultra identified SS convergence points– Allies turned Donitz C3 system to their

advantage tracking HF transmissions (DF)– Now able to intercept Wolf Pack & attack– Brits attack from the air if Sub caught on the

surface

– Finally: US was able to produce more Liberty ships per month than SS could sink

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The Air War- Strategic Bombing• RAF Bomber Command => Strategy & Target priorities:

– Role of AM Harris & his strategic focus:• Target high concentration of civilian population (area bombing)

– Day vs. Night time operations• Analysis results: precision bombing too hard

– Hard enough to even hit cities at night (let alone point targets)

• USAAF Op Strategy: US vs. British target priorities– Precision Bombing (day) vs. Area Bombing (night)– Target selection (divisive among allies)

• US target focus: German aircraft industry => ball bearings• US Strategic objective: key economic nodes

• Casablanca Meeting => compromise (of sorts) achieved:– AM Harris: insisted on area bombing (cities)– USAAF: precision day strikes on German industry

• (But no truly common approach agreed to)

– Reality: Allied strategy based primarily on tactical capabilities• If the Allies were to advance beyond Strategic Bombing- what was required first?

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Mobilization & Power Projection • US mobilization presented several challenges:

– 1st & foremost: recruit, equip, train, deploy, &employ manpower

– 2nd : transform economic & industrial might into war economy

• Great Britain’s mobilization involved greater sacrifices:– All British citizens & industry fully dedicated to the war effort:

• Serving in uniform, Home guard, or enduring Blackouts and the Blitz,

• Waiting in Long lines for scarce goods, rationing, and paying high taxes

• Germany’s mobilization was seriously flawed:– Hitler had delayed consolidation of early gains=> war economy– Slow to fully mobilize & also opposed to women in work force– Slave labor inefficient at best & vulnerable to sabotage at worse– Inadequate $$$ & industrial base & shortage of raw materials– Allied strategic bombing also caused inefficient decentralization

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Assessment

• US entered WWII because of a major strategic miscalculation:– Japan: surprise attack on Pearl Harbor aroused sleeping giant

– Then Hitler: declared war on US• (Played into FDR’s political & military plans- Germany first strategy)

• After all said & done => victory depended on what?– Successful ?__________ of allied industrial & economic power

– +Translation of vast industrial potential into military power

• And then ... =>– Transport and project allied power into where needed– Time and U-boat threat: major challenge to this objective

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Assessment- 2

• Britain and US must there4 tame Submarine threat first:– Brit/US must rely 1st on strategic air power projection into

Germany– Only power projection tool available initially –why?

• 1. Germany controlled ?_____- no foothold available to launch operations• 2. Allies not ready to invade Europe yet• But allies had to do something against Germany

• How well did Allied strategic bombing do?• Allied strategic bombing ?______ as Operational objective

– (Although gradually did pose threat to Nazi war $$$)– At too high cost in men, time, and A/C for limited benefit gained

• Allies major accomplishment?– Total ?______________ of all its resources =>

• Mobilized on grand scale in a very short time frame– Key element to war’s final outcome – over time

Back-up Slides

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RAF Bomber Campaign

• Bomber Campaign at height (1943-44):– British workhorse: Lancaster Bomber– Operational focus: Ruhr River Valley – Key target: Ruhr Dams (high casualties)

• Major RAF Bomber targets included:– Hamburg Firestorm (30-40K killed)– Peenemunde R & D station– Berlin (result in very high casualties)

• Technological improvements helped reduce German radar interceptions:– “Windows” (?)

• Bails of aluminum strips reflect radar– NTL- effective air defense tactics of Gen

Kammhuber result in high casualties

• Bottom line:– British campaign too costly => suspended

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American Raids on Germany• US precision daylight Targets:

– USAAF 8th AF workhorse during war: B-17• P-40 & P-51 Fighter escort

• Operational & tactical focus:– Ruhr, Regensbury, Schwenfurt

• Aug-Oct’43: unescorted deep daylight raids into Germany– US suffered high casualties => – Result: 8th Air Force called off deep

penetration raids

• Target reality: Ball bearings held in large backlog– Easily obtained from neutral nations (Swiss

& Swedes)– Also substitute easily made rollers

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Luftwafffe • Goering’s role: could make Hitler laugh (& the Army cry)

– Luftwaffe lacked effective leadership

– Two major mistakes by Hitler & OKW regarding Luftwafffe?

• 1. Diverted JU-52s to transport Troops in Tunisia:– (Shut down bomber pilot training!)

– (Eating your young- future aircrew replacements?)

• 2. Eastern Front – Stalingrad:– 6th Army denied permission to withdraw – why? Goering’s role?

• Convinces Hitler Luftwaffe can re-supply 6th Army @ 600 tons/day

• Dooms 6th Army as a result

– Luftwaffe did provide heroic CAS to 6th Army• But with time => heavy losses mount up

– After Sept ’43: Hitler shifts bulk of air power to West:• By then-Allies controlled all airspace over Eastern Front

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The Air War- Strategic Bombing

• RAF Bomber Command => Target priorities:– Role of AM Harris & his strategic focus:

• Target high concentration of civilian population (area bombing)

– Day vs. Night time operations• Analysis results: precision bombing too hard

– Hard enough to even hit cities at night

• Luftwafffe priorities:– Gain Air superiority trumps strategic Air Defense

• Against RAF Bombers

• Kammhuber’s role limited defense system– Night fighters effective in attacking RAF Bombers– Germany’s overall lack of support for air defense– Focused on offensive strikes

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USAAF Operational Strategy

• Contrasted priorities: American vs. Brit targets– Precision Bombing (day) vs. Area Bombing (night)

– Target selection (divisive among allies – why?)• US: German aircraft industry => ball bearings

• US Strategic objective: key economic nodes

• Casablanca Meeting => compromise achieved:– AM Harris: insists on area bombing (cities)

– USAAF: precision day strikes on German industry

– (But no common approach agreed to)

– Allied strategy based extensively on tactical capabilities

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Mobilization & Power Projection

• US challenges to mobilize- summarized as follows:– Recruit, equip, train, deploy, & employ manpower

– Harness economic & industrial might to war economy

• Great Britain’s mobilization involved greater sacrifices:– By 1944 24% of its labor were dedicated to the war

– Civilian Defense Industry dedicated almost 18% of its capacity

– All British citizens fully involved in war effort:• Blackouts, Blitz, Quarters shared with troops, Home guard duties

• Long lines, scarce goods, Rationing, high taxes

• Major problem: Brit antiquated Industrial infrastructure:– Motor industry => poor vehicle & tank performance

– Especially telling during North Africa campaign

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Mobilization- Germany

• Inadequate economic & industrial base– Shortage of raw materials

• Delay in consolidation gains => war economy:– Slow to enact full mobilization– Hitler’s ideological problem with women workers

• Hitler’s hang-up prevents half population from helping

– Slave labor inefficient & definitely unmotivated:• Sometimes even sabotage production

• Impact of Allied strategic bombing:– Decentralization of production =>

very inefficient• Less produced with more time

required to do it

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Enigma & Ultra

• British capture of U-Boat & its Enigma– Impact: Brits able to read enemy’s plans – (Photo: Guderian HQ w/Enigma machine)

• Bletchley Park’s role– Advantage afforded to Allies by decrypted operational

directives– Decrypted product called: Ultra

• Allies finally able to counter German SS threat- also through HF/DF:– Frequent US-Brit cooperation & intelligence breakthroughs

• Ultra identifies SS convergence points• Allies turn Donitz C3 to their advantage• Now able to intercept Wolf Pack & attack

– Finally: US able to produce more Liberty ships than SS could sink