The Travises who had survived were the most purely stubborn people on earth, the kind who relied on their backbones when their wishbones were broken.
If an adversary didn't target our power plants but they did target the core routers, the backbones that tie our internet connections together, entire parts of the United States could be cut off. That would have a tremendous impact on us as a society and it would have a policy backlash.
If you look at Gothic detailing right down to the bottom of a column or the capital of a column, it's a small version of the whole building; that's why, like dating the backbones of a dinosaur, a good historian can look at a detail of a Gothic building and tell you exactly what the rest of the building was, and infer the whole from the parts.