“THE DESTROYER KILLER’S LAST DIVE”

How USS Harder altered the Battle of the Philippine Sea — and the legacy left behind

Japan’s mobile fleet at Tawi Tawi was the largest concentration of naval power since Midway:

4 battleships (including Yamato)

9 carriers

15 cruisers

28 destroyers

Operation A-Go relied on precise timing and coordinated movement.

But on June 9, 1944, after losing four destroyers in four days, Admiral Ozawa did the unthinkable:

He ordered the fleet to leave six days ahead of schedule.

This decision — made out of fear of Harder — shattered Japan’s entire war plan.

How One Submarine Disrupted an Empire

Leaving early meant:

Japanese reconnaissance planes burned fuel too fast

Destroyer screens were scattered and unorganized

Supply ships fell behind schedule

Carriers entered the battle at the wrong time, in the wrong formation

The result?

The Great Marianas Turkey Shoot.

On June 19–20, 1944:

American pilots shot down 376 Japanese aircraft

Japan lost three carriers

75% of its naval air arm was wiped out

The Imperial Navy never recovered

Admiral Lockwood later wrote:

“Harder’s fifth patrol was the most strategically important submarine operation of the Pacific War.”

Without Dealey’s attacks, the Battle of the Philippine Sea would have unfolded very differently.

The Final Patrol — August 1944

After Harder returned to Fremantle, Dealey trained new officers in his aggressive “down-the-throat” doctrine — tactics that would later be used by dozens of U.S. submarines.

On August 5, 1944, Harder headed out again — her sixth patrol.

At first, it went well:

Harder and her wolfpack sank four cargo ships

Then two coastal defense frigates

Then another escort vessel

But Japanese intelligence had been tracking them.
And on August 24, off Luzon, two Japanese anti-submarine escorts — CD-22 and PB-102 — moved in for the kill.

At 0520, Harder crash-dived.
But her bubble trail on the surface gave her away.

CD-22 swept overhead and dropped a pattern of depth charges perfectly aligned.

Three detonated within 50 feet of Harder’s hull.
Her stern flooded instantly.
The bow pointed upward as the submarine struggled to surface.

Dealey ordered “Blow all ballast!”

But it was too late.

A second attack ruptured the pressure hull.
Water surged into the control room.
Power failed.
Lighting died.
And at 600 feet — far beyond safe limits — Harder imploded.

All 79 crewmen were killed.

USS Hake, submerged nearby, listened helplessly as Harder died in the darkness.

Legacy of a Legend

Commander Samuel Dealey was awarded the Medal of Honor posthumously.

Harder received:

Presidential Unit Citation

Six battle stars

A place in submarine warfare history unmatched before or since

Her motto — “Hit ’em harder” — still echoes across U.S. Navy tradition.

Between June and August 1944, submarines inspired by Dealey’s doctrine sank:

38 Japanese destroyers

214 warships in total by war’s end

A tactic once considered insane became standard in aggressive submarine warfare.

The Wreck Found — 80 Years Later

On May 22, 2024, the Lost 52 Project discovered USS Harder sitting upright on the seafloor at 3,750 feet.

Her hull — except for the fatal damage — remained intact.
She is now a protected war grave.

For the families of the 79 men aboard, the discovery brought long-awaited closure.

Why This Story Matters

Harder wasn’t just a submarine.
She was proof that courage and ingenuity can shatter doctrine, terrify an empire, and alter the destiny of entire fleets.

Her crew came from 38 states:
farmers, mechanics, college boys, first-generation immigrants.
22% of submariners in WWII would die — the highest casualty rate of any American branch.

They knew the risks.
They served anyway.

And when their captain told them to charge a destroyer head-on…
They didn’t hesitate.

Today, naval academies still teach Dealey’s patrols — not for their torpedo math, but for the leadership lesson that defined his legacy: