It was a war of all wars; World War 2 had many players and there were many successes on all sides. But, there were a ton of military mistakes also made by both allied and axis military machines.
Have you ever considered what the world would be like if Germany or Japan would have been victorious? The world as we know it would be quite different.
Many people were killed and a vast amount of infrastructure was destroyed during World War 2. Much of this could have been lessened if some mistakes were not made. But, it is what it is. And hopefully, both our military and our ally’s military have learned some major lessons from the mistakes made.
In today’s post, I am going to give you my opinion of the top 20 military mistakes of World War 2. I am looking at all mistakes from both sides. I will start with #20 and move up to the #1 mistake made.
No sense to leave you sitting on that bed of curiosity…
#20: Hitler’s Obsession With Super-Weapons
While he nearly had some mighty weapons developed that could have possibly won the War, Hitler was totally obsessed and neglected supplying his troops with many of the basic weapons and equipment they needed to be victorious.
Some of the super-weapons Hitler was spending money on were:
Super-guns that could hit any European target
Vertical take-off and landing fighter planes
U-Boats that would fire ballistic missiles
The stealth bomber
and many more
#19: Invading The Philippines
Sure, the Philippines was a U.S. territory and the Japanese had taken it, but when the United States used resources to invade the Philippines, it really did not help us in the battle against the Japanese. Landing strips in the Philippines were too far from Japan to help, and it did nothing to stop Japanese aggression. We used too many resources that could have been utilized in better locations.
I know I will probably get some hate mail over calling this a mistake, but when you look at it in strategic terms, you have to call it like it is.
#18: Treatment Of Natives By Axis Invaders
Both Japan and Germany made major mistakes in the treatment of natives of certain areas they invaded. If they would have treated these people better, they would have made allies of them.
When Japan took the Philippines, the Filipino people considered they may be their rescuers from the “white man.” But the Japanese enslaved them brutally and they realized the white man was much better.
The Russian people were treated very bad under Stalin and if the German Nazi’s would have used a different approach, they would have gained their trust. But the Russian peasants realized the German’s were more brutal than Stalin.
#17: Not Using The Mosquito To Full Capability
The British RAF had the fastest bomber there was. The Mosquito bomber was made of wood and only had 2 crew members. This bomber should have been heavily produced and used consistently, but it wasn’t. The War would have been shortened greatly if it would have been the primary weapon of the Royal Air Force.
#16: Exercise Tiger
This was a major mistake that cost lives needlessly. The idea put forth from Eisenhower was a test run before the D-Day invasion. But American and British were not on the same radio frequencies.
British warships broke down and German E-boats attacked their convoys. Soldiers were not taught the proper way to wear life vests and drowned.
To add to the confusion, live shells were used to hit the landing beach and allied troops were killed from friendly fire.
To be blunt… it was pure stupidity.
#15: The Disbelieving Stalin
As German forces built up at Russian borders, Russian counselors told Stalin they were going to invade. He wouldn’t have it and even threatened with death the next person who told him this.
While Stalin slept, Germany invaded and killed many Russian soldiers.
#14: Russia Deployment Without Protection
To this day, no one understands what Stalin was thinking. He deployed vast amounts of equipment and troops to the border without protecting any of it. When German forces invaded, they found many supplies just covered with tarps and stacked on pallets. These equipment and supplies gave German forces more ability to move forward into Russia.
#13: Hitler Not Conferring With Japan
Just days before Hitler ordered the invasion of Russia, Japan had signed a non-aggression pact with Stalin. Russia was able to move troops from the East to the German invasion. If Germany would have conferred with Japan, the invasion of Russia just may have come out much differently.
#12: Underestimating Japan
This one is a mistake of the United States. When it looked as if Japan would attack U.S. interests, military advisers said that Japanese pilots were blind and could not fly at night. They just simply underestimated Japan in many ways and it cost many American lives.
#11: Not Destroying Ploesti Early
The war with Germany could have been shortened greatly with one wise move: bomb and destroy Ploesti, Romania. This was the main supply of oil for the German military, but they left Ploesti alone for much of the War.
Ploesti was well protected, but with the Royal Air Force’s resources, and the Mosquito mentioned earlier in this post, it could have been destroyed.
#10: The Dieppe Raid
This huge mistake cost thousands of Canadian and British lives. The idea was to send Canadian and British troops on the French coastal city of Dieppe. It was a total failure. The Germans were prepared and killed 1,000 + troops, took 2,000 + troops prisoner and destroyed over 100 aircraft.
#9: Hitler Declaring War On The United States
For the biggest part, the U.S. had more important “fish to fry,” but Hitler just had to bring us into his evil plan. By declaring War on the United States, our hand was forced. If Hitler would have not done so, he just may have been able to conquer Europe.
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#8: Not Attacking Germany Immediately
What was Great Britain and France thinking? When Germany invaded Poland in 1939, both countries declared War on Germany, but they didn’t move. If they would have immediately attacked Germany, I believe there would have been an end to the German aggression much quicker.
#7: Operation Market Garden
This Operation was a 2 part phase… hence market & garden. The idea was to take a long corridor from Belgium through the Netherlands into Germany and win the War.
The Market phase was the drop of allied airborne troops to take major bridges. This phase went somewhat well, but the Garden phase led by British Field Marshal Montgomery did not. He was to drive British tanks through the corridor, but he gave up.
It was a failure that cost many lives and Montgomery’s respect.
#6: The German Bombing Change
The Germans were successfully bombing Royal Air Force airfields and putting a huge damper in their ability to get their fighters and bombers airborne.
Suddenly, the German military changed tactics and started bombing London. This gave the RAF time and resources to regroup. If the Germans would have kept their onslaught on RAF fields, the War would have been quite different.
#5: Italy Invasion Of Greece
When Mussolini decided to invade Greece, it was an error that hurt Germany. Because Italy could not defeat the Greece forces, Germany had to send valuable manpower to help Italy conquer the country. Those troops could have been used better in other locations.
#4: Dunkirk
The German’s had the British surrounded at Dunkirk, but Hitler decided not to attack except with bombers. This gave a chance for many soldiers to escape and live to keep fighting. This was an extreme error by Adolph Hitler.
#3: Japan’s Attack On Pearl Harbor
When Japan attacked Pearl Harbor, they brought the lion out of us. Yes, they won a battle and killed many, but there is a good chance we would have never “nuked” them if they wouldn’t have attacked Hawaii.
#2: Not Having A Complete Maginot Line
Built by the French, the Maginot Line was a defensive barrier built on the French borders with Germany, Switzerland and Luxembourg. The error was not working with Belgium and extending it all the way to the coast. German forces came through Belgium in a devastating way.
#1: Germany Invading Russia
This is my opinion of the top mistake. If Germany would have left Stalin and Russia alone, they probably could have conquered all of Europe. When Germany invaded Russian lands, Stalin would not stop for anything until he completely wiped the German forces out.
Final Thoughts
As you can see, I listed mistakes from many different sides. What are your thoughts? Do you agree, or would you have listed some other mistakes or put them in a different order?
We appreciate your comments, so feel free to post them in the section below. If you have any questions, you can also post them here too.
Thank you.

Chuck Holmes
Former Army Major (resigned)
Publisher, Part-Time-Commander.com
Email: mrchuckholmes@gmail.com
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