Primacord fuses are built into bridges which can be detonated to collapse on top of railways to halt any advancing troop columns. Their main highways can, in a pinch, be converted to landing strips for jet aircraft that are hidden nearby in bomb-proof underground bunkers.
The Swiss are nobody’s fool. There is a reason they’ve been able to stay neutral through two world wars. Maybe that’s the secret to getting a highway bill passed: give it to the Pentagon.