John von Neumann was in favor of a preventive nuclear attack against Russia. Do you think that if von Neumann was still around and thought that Google would within 5-10 years launch a doomsday device he would refrain from using violence if he thought that only violence could stop them? I believe that if the U.S. administration was highly confident that e.g. some Chinese lab was going to start an intelligence explosion by tomorrow, they would consider nuking it.

There is some truth to that, especially how crazy von Neumann was. But I'm not sure if anyone would be launching pre-emtive nuclear attack on other country because of AGI research. I mean this countries already have nukes, pretty solid doomsday weapon so I dont think that adding another superweapon to its arsenal will change situation. Whether you are blown to bits by chinese nuke or turn into paperclips by chinese-built AGI doesn't make much difference.