In the long term, military power is proportional to economic power (i.e. aggregate GDP). Therefore in order to protect the constitution and the USA I want the aggregate economy to grow.
I also believe labor specialization has been one of the most important factors in global and US economic growth. Why should I care if my TV is made in Korea or Kansas? The people of Kansas have other things they make.
You do realize imports reduces GDP right? GDP = C + G + I - (Imports - Exports). That again doesn’t even count the impact of loss of wage base and tax base with lowering the money velocity, which also lowers GDP.