Realize we have a very, very large country, and it's chock full of forest, so plenty of lumber resources to do such things. Other places use different materials/techniques/etc which are mostly based on what resources they have easy (read: cheap) access to.

Also not all of the US uses timber framing, for instance, in costal florida, it's not uncommon to have concrete walls that are framed with sheerwall inside, so they can survive a hurricane.