No battleship is still in service on this planet. A few of them are still around, but they are either museums or they are covered in algae at this moment. Correct me if I am wrong, I do not recall any country had built a single battleship after WWII. Battleships were expensive to build, yet it was shown to be an ineffective weapon in naval warfare even in WWII. There were very few ship to ship battle took place where battleship played a role. Majority of the combat were done by aircraft launched from aircraft carriers. Thus since WWII, capital ships had shifted from battleships to carriers.
Back in the old days, in theory the ship with the thickest armor and the biggest guns will win the battle. Nowadays much smaller ships like destroyer, frigate, and even corvette can carry deadly anti-ship missiles. Basically any smaller ship carrying missiles can pose a deadly threat to the much more expensive battleships. So why spend so much money to build something can be easily sink?
