Just a couple of observations:
*
McKinley is believed to be an anglicization of the Gaelic nickname
Mac an Leigh, meaning something like "son of a leech."
* There is historical precedent for motorways being used as aircraft runways, notably in Germany during World War II. I think FHWA's highway history pages have (or at any rate used to have) an account of how this led to the received idea that Interstates were required to have one straight mile in every five. In actuality, very long tangents are considered problematic from an alignment design perspective.
Returning to the topic of this thread: I've long suspected the received idea that the US highways were built with 50% federal, 50% state funding is a grossly oversimplified account of how cost-sharing evolved over time.