The SSS Ranked Villain's Return - Chapter 344: Bread

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.

A recurring nightmare afflicted Khan's nights since the Second Impact. His dreams replayed the scenes of the crash of the Nak's spaceship, an alien race that the humans had defeated five hundred years ago.

“Great Mr. Chen Yu, you were successfully elected as the leader of the human race last night. Is there anything you would like to say to the world?”Chen Yu, bewildered, woke up and hadn't even put on his clothes yet. He replied, “I have no idea, I just woke up...”

This is a prequel to the anime movie To Aru Majutsu no Kinsho Mokuroku – Endymion no Kiseki.

Just before the completion of the Academy City space elevator “Endymion”, the main characters Kamijou Touma and Index encounter a level 0 girl named Arisa. The Magicians are after Arisa, and they attack Academy City. A female leader named Shattoaura leads a unit from Academy City against the attack. Kamijou and Index learn from Stiyl that Arisa is key to a brewing war between the sides of Magic and Science. When science and magic cross paths, the story begins with Endymion as its stage!