Why would a nation strive to increase the challenge it faces? Was the original challenge so contemptibly small that we needed to double and triple it, to give our moral fiber a work-out?

Perhaps the idea is that by enlarging and then defeating this challenge, we shall be a better nation. In that case, if challenges are so good for us, why not create a few more?

I suggest flooding some low-lying cities; causing landslides on inhabited hillsides with well-placed explosive charges; letting loose a few dangerous pathogens … Or why not set off a nuclear weapon or two in populated areas to see how well we meet the challenge of swamped hospitals and mass evacuation?