I heard the most interesting theory that only the US has nukes, could it be true?

If the Soviet Union really had around 15,000 at the height of the cold war and lots of "suitcase nukes" that were lost or went on sale to the black market why hasn't a single nuke been used in aggression since WW2? Why didn't a rogue general ever launch one? Why didn't a rogue scientist ever build and launch one? And surely terrorists would have gotten hold of one! Apparently the powers that be collaborated to fake the Cold War to scare the public out of money and power, the nukes that the Soviets showed off were actually made of wood, and every real nuclear test was staged by the US, who acted as a proxy. Like the recent case of North Korea testing a "nuke" underground, they didn't even have the technology for uranium enrichment and there was no radiation detected, it has all the signs that it was staged using large amounts of dynamite buried underground, and was done with the aim of scoring concessions (AKA economic blackmail) and increasing their global influence.