[walrus01]

Sort of a related tangent to the "the internet was designed by ARPA to survive nuclear war" trope that is trotted out occasionally...

It's NOT that the Internet specifically was designed or intended for this, it was a research network. The pre-existing AT&T Long Lines network which carried telephone traffic around the US48 states also carried the DoD's AUTOVON network data links for their own phone system, and data links between things like SAGE direction centers.

Many of the cold war era hardened AT&T Long Lines bunkers, underground sites, special buried mountaintop sites and such all pre-date the earliest days of the ARPANET.

There's mountain top long lines sites out there now that couldn't be duplicated for less than $50 million. Money was thrown at this in quite a profligate manner - same as money was spent on various early generations of ICBMs, strategic air command 24x7x365 standby and patrols, the DEW line, and such.

In the era before inter-city singlemode fiber optic cables were a real operational reality these places were absolutely crucial.

The data links between sites in many cases rode on top of these networks in the earliest days of IP.