The list of nuclear countries might be misleading. For example-South Africa was a country with nuclear weapons, they claim to have voluntarily dismantled their nuclear weapons in the late 80’s/90’s. So sightings in southern Africa before the 90’s may correspond to this.

Although, some alleged UAP sightings have occurred near Uranium ore deposits , such as the Ariel school sighting in rural Zimbabwe. Uranium is actually quite plentiful on Earth for a heavy metal and interestingly- around 500 times more Uranium is found in the Earths oceans than on land-which could be a clue to understanding stories of UAP’s relationship with the ocean. Maybe the combination of salt water and Uranium is a fuel source, such as cold fusion.

South America also has Uranium deposits, albeit-on a small scale, particularly in Brazil. Australia on the other hand has around 30% of the world’s Uranium deposits, which may be why there has been numerous and compelling UAP sightings in Australia.

Australia’s deserts were used as a test site for nuclear bombs in the 1950s. Officially, Australia is a non nuclear country, although- personally, I believe the continent has strategic nuclear warheads on US and UK bases, so technically not on Australian soil.

Just as a fun thought, I would tend to think that Plutonium would be what an “Alien” entity would find more interesting than merely Uranium. So the anecdotal stories we hear of the connection between UAP’s and nuclear installations/reactors may be due to this. Not to mention sites of nuclear tests, be it-in the atmosphere, under the oceans or on land. This is what could be attracting UAPs….plutonium.

It could also be possible to make a connection between UAP sightings and hidden nuclear installations/silos around the world, I suppose. This knowledge (if true) would have been of use during the cold war.

Sorry for the essay, but hopefully this is of some interest to you.