Nuclear bombs are immoral and should be illegal. They are just as great, if not a greater, existential threat than climate change and the world would be better off without them. Just making my stance clear.

Right. Despite only two bombs being used in war, nuclear bombs have been detonated thousands of times and in doing so have wreaked devastation on the places where they were tested. They do have the power to turn a paradise into purgatory.

In this footage you’ll get to see what happened when the largest nuclear bomb ever built was tested by Russia.

Though the bomb detonated nearly 2.5 miles (4 kilometers) above ground, the resulting shockwave stripped the island as bare and flat as a skating rink. Onlookers saw the flash more than 600 miles (965 km) away and felt its incredible heat within 160 miles (250 km) of Ground Zero. The bomb’s gargantuan mushroom cloud climbed to just below the edge of space.

https://www.sciencealert.com/russia-declassifies-footage-of-the-most-powerful-nuclear-bomb-in-history?

For most of the Cold War nuclear powers had similar thinking or doctrine but that is no longer the case. Pakistan, India, Israel and North Korea do not think about the use of these weapons in the same way. And there are efforts to make them more useable not less.