“... the United States has made few laws restricting the export of our cultural property, limiting such laws to the protection of historically, architecturally, or archaeologically significant objects on land that is owned, controlled, or acquired by the federal government...” (James Cuno, 'Museums, Antiquities, Cultural Property, and the US Legal Framework for Making Acquisitions', Who Owns the Past?, p. 146)
Yesterday the City of New York declared Keepers Self Storage as landmark making it one of 23,000 buildings under the jurisdiction of the NYC Landmarks Preservation Commission. The building is considered worthy of municipal protection because it had manufactured a well-known brand of dog food in the 1920s.
Cuno is technically correct. New York City made the law rather than the federal legislators. It isn't illegal to export antiques from landmarked buildings — but removing architectural features changes a building's appearance and is a crime. Thus Cuno is basically wrong. I'd guess zoning and landmark designation are the primary legal means to restrict commerce in cultural property in the USA.
Landmark designation in NYC is often fraught with controversy with the property owners (usually called 'Developers' in news accounts) arguing that their property isn't culturally important against zealots claiming that allowing owners to build on their own property would destroy neighborhood character. The character is said to define the residents and somehow belong to everyone in the district.
(By now my readers should figure out that I'm posting stuff hoping to get comments. I could write about non-controversial stuff but then I wouldn't know if anyone is reading. So in the comments section I'd like to hear your thoughts, pro or con, about legal protection of US architecture. Also, if you don't like political stuff and wish I'd get back to discussing digitizing and hyperlinking coin books feel free to post that too.)