What are the most costly mistakes ever made in history?

1. The land is useless.​

Alexander II of the Russian Empire thought Alaska was just a useless ice land, so he sold it to America for a very cheap price (7.2 million USD) (which would be worth 1 billion dollars today), but now Alaska is one of the most important areas in the world with an estimate of more than 50 billion dollars.

(Russia sold Alaska because it was under pressure from the Crimean War. Russia was afraid that England would be able to infiltrate Alaska through Canada, especially since the area was remote and difficult to defend. FYI, the number of Russian residents in Alaska at that time was not even more than 1000 people, so this price was enough to break even for both of them. Alaska's utility value came from oil, and this was only discovered in 1902).

2. The wrong tools can cost more than 720 billion USD in losses.​

The Chernobyl explosion is arguably the most expensive mistake ever made due to the use of faulty equipment, so it could be one of the most expensive mistakes in the world.

3. The heaviest submarine in Spain.​

The Spanish government spent about 1.75 billion dollars to build a new submarine (Isaac Peral), but after the construction was completed, they realized that the submarine was too heavy to operate in the water, so they rebuilt the ship and lost 1.75 billion USD.

4. Expensive ships that unfortunately sank too soon throughout history.​

Vasa , a $200,000 Swedish ship in the 17th century (it would be more expensive now) that was built to be the strongest ship in the world, but unfortunately, this ship sank immediately while still in the shipyard.

5. Beirut explosion.​

The Beirut explosion is one of the biggest mistakes in history. You will say that this is not history. Not really, the reason for this explosion has been around for 6 years and this explosion caused more than 15 billion dollars in damages, including human lives…

6. Europeans who killed all the cats.​

(Religious disgrace) After the pope ordered the people to kill all cats because they considered them to be the incarnation of the devil, the Black Plague spread throughout Europe and killed millions of people, finally in the 14th century they imported cats from the Middle East and Africa.

7. Anglo-Spanish War​

This war caused Spain to lose all their colonies in Africa and America, including their ships and treasures. This was all due to Spain being proud of its strength and power.

Thank you for your attention.