Its dangerous and has gargantuan risks attached to it. The americans stopped project Pluto for exactly that reason.
I find it quite irresponsible how easy Russia takes those risks for their own population. They obviously learned nothing from Chernobyl. And there are far worse areas in Russia
regarding fallout and nuclear waste. Sunken nuclear reactors that leak radiation into barrent sea. Areas like in Ural mountains that often release radioactive fallout. Now this exploding engine.
I have a question here, France stands for nuclear power. I see it as important energy scoruce. We have countless nuclear power plants, nuclear powered submarines ect. But never an accident on that scale.
What do we right that Russia does wrong?
Regarding that nuclear engine...the Concorde was banned to fly over land with supersonic speeds because the sound emissions created by it.
No nation will allow a aircraft fly over it with radioactive engines. So consider this a dead end development.
It also adresses another factor. Such aircraft have the ability to poison large areas of land. They obviously should not be shot down over allied territories so in case of war they must be destroyed while still over enemies land.