Final answer:
Business leaders like John D. Rockefeller and Andrew Carnegie were sometimes called robber barons because they used ruthless business tactics against their competitors.
Step-by-step explanation:
Business leaders like John D. Rockefeller and Andrew Carnegie were sometimes called robber barons because they used ruthless business tactics against their competitors. They were known for practices such as forming monopolies and trusts, driving competitors out of business, and paying low wages to workers. While their actions contributed to the growth of the US economy and the creation of new industries, their methods were often seen as exploitative and unfair.
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