The U.S. has a pretty big parts industry, but it varies a lot by sector. It's quite strong in heavy machinery, for example, where domestic suppliers have a majo

The U.S. has a pretty big parts industry, but it varies a lot by sector. It's quite strong in heavy machinery, for example, where domestic suppliers have a majority marketshare in both the market for the machinery itself, and the parts used for building and maintaining said machinery (and the tooling for the machines that build those machines... etc.). There are various ways to slice it, but if you take the broad sector of "machinery and equipment" as defined by the U.S. Department of Commerce, domestic suppliers have about a 60% share of the U.S. market overall: http://selectusa.commerce.gov/industry-snapshots/machinery-and-equipment-industry-united-states.html http://selectusa.commerce.gov/industry-snapshots/machinery-a...