I see. To answer your question, it isn't about economy but politics and power. Having a more diversified economy makes you less dependent on the whims of others

I see. To answer your question, it isn't about economy but politics and power. Having a more diversified economy makes you less dependent on the whims of others, albeit it can be at the cost of overall efficiency. I guess everybody does the same as well, we insist in having some understanding of other skills so that we aren't at the mercy of others.