I think you should reframe the second part a little bit. Sure, it's not really a major economic school utilized anymore, but to call it a "failure" is a bit disingenuous as many major powers DID thrive (at many's expense) on it for centuries and it was essentially the economic basis of many colonial endeavors. As far as the specific economic and historical issues with mercantilism's execution, I'm going to defer to people more knowledgable in economic history than myself.

This sounds like a homework question and is frankly really really easy to look up.

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