It’s often relatively inexpensive to mothball a production line (relative doing heavy lifting) and sometimes you can even keep parts of it operational making things for other uses.
The production line is one thing, the supply chain is quite another. When the Department of Defense shut down F-22 production they mothballed the Lockheed Martin final production line (although there were some gaps and missing tooling). But then when they looked into restarting production several years later they found it was just impossible because the supply chain had disintegrated.
yes, but there is only a single line for Honeywell AGT1500, which is a bit ridiculous. There should be a second factory on another continent in case of a natural disaster.
"Honeywell AGT" being the "Abrams gas turbine", a/k/a the powerplant for the M1 Abrams tank.