Final answer:
The market expansion strategy that could be used for an American company wanting to diversify within the United States rather than going global is country and market diversification.
Step-by-step explanation:
The market expansion strategy that could be used for an American company wanting to diversify within the United States rather than going global would be Country and market diversification. This strategy involves expanding into different regions or markets within the country, targeting different customer segments or offering new products/services to reach a wider audience. Instead of focusing on one specific market, the company diversifies its operations to reduce risk and tap into different opportunities within the United States.