Parts that you can easily start up quickly are fine to be outsourced, and indeed, to pay higher costs here at home to make a simple part that can be outsourced is, to use your term, "traitorous."
But it would be equally dangerous to allow the U.S. commercial aircraft or shipbuilding industry deteriorate because when we need those planes---possibly to fight the Chinese---we need them. Now, that raises real-world questions, and not just polemic sound bites. For example, how MANY commercial air manufacturers should we subsidize/support? Any? All? How many shipbuilders? Our solution to the present has been to have one layer of competition (i.e., at least two in each category), so we have EB and Newport News. If there are more, fine, but we don't want to be stuck with one, nor do we want to subsidize 50.
This has resulted in some mergers that I think are pretty sensible, because they allow the U.S. to subsidize one company on the basis of its major product (say, rockets) while nevertheless keeping its minor products (say, airframes, or jet engines) "in play" enough that it can be competitive.
It is, however, impossible to be totally self-sufficient, particularly in some national defense items, because the U.S. simply has NO natural resources of chrome, titanium, or even large resources of bauxite, lead, tungsten, diamonds, and so on. So one must embrace free trade if one wants an army or navy, unless you want an army or navy of the 1700s.