Airships are cool but are a large easy target.
With the incorporation of superchargers and turbochargers in aircraft engines (and an overall increase in power), this drastically increased the altitude limits for propeller aircraft.
When the airships could still fly higher than aircraft, that reduced their vulnerability to direct attack.
In the context of transportation planes seem to have significant issues dealing with loons wielding laser pointers. So unless you classify those as military technology you will have a hard time finding something cheaper and easier to get your hands on.