The US has vast timber forests, so it is inexpensive, and timber (or steel) framing works well for earthquake resistant construction. A large part of the US is a seismic hazard zone and the building regulations reflect that. You can find older neighborhoods with unreinforced masonry throughout the US but those date from a time before they had modern building regulations and before the extent of earthquake risks were fully understood.
The US has vast timber forests, so it is inexpensive, and timber (or steel) framing works well for earthquake resistant construction. A large part of the US is a seismic hazard zone and the building regulations reflect that. You can find older neighborhoods with unreinforced masonry throughout the US but those date from a time before they had modern building regulations and before the extent of earthquake risks were fully understood.