In national security, the term "critical infrastructure" is also extremely broad (although it should be less inclusive as not all infrastructure should be considered critical) and includes support, e.g. for banking, and other such processes of questionable merit. One issue is the necessity of means of protection, and of accounting, in increasing value of life. Advocates of a broad definition usually argue that without these "critical" systems, the rest of the infrastructure is looted, burned, or not safe to use.
Another issue is whether means of persuasion, like computer or radio or televisiontechnology, can qualify as infrastructure in any sense, as it is more belief-sustaining than life-sustaining. The arguments parallel those for means of protection, with conservatives generally asserting that belief in a common view of reality, especially in emergency response, is critical to survival.
Typically, infrastructure in this context denotes two general groups of support systems: transportation modalities (roads, rail, etc.) and utilities. These typically compose both public and private systems, and some ambiguously held in common.
Infrastructure may also refer to necessary municipal services, whether provided by the government or by private companies. If provided by nature, e.g. the flow of a river, they are called nature's services and are distincted (at least in economics) as the product of natural capital. This may be augmented or directed by infrastructural capital, e.g. a dam or canal or irrigation ditch. In general what is called infrastructure tends to be very embedded in the natural landscape and cannot be moved from place to place. Even municipal services rely necessarily on fixed locations, e.g. fire stations in central positions in a city, transmission towers on tall buildings, etc..
