Personally I don't think its either of those, but if I were to choose one it would be the third. Those who live in glass houses should not throw stones.
It would be difficult and near impossible to see this as a single phenomenon and for it not to be seen as part of a broader process of colonization and imperialism at the time. However, one distinct feature of the colonies in North America was that there was massive migration of Europeans to these colonies whereas in other colonies at the time the migration was not as substantial. <span />
They were all afraid. They had more and more weapons but were more and more afraid because they knew that if any of them attacked, the others would retaliate and that monstrosities would be committed. They had many nukes but nobody used them out of fear of what the other one would do since they wouldn't be able to defeat the opponent before he launched his nukes.