Anheuser-Busch InBev is the Belgian company that produces Budweiser, which has a large market share in the

Question:

Anheuser-Busch InBev is the Belgian company that produces Budweiser, which has a large market share in the U.S. beer industry. According to an article in the New York Times, "Anheuser-Busch (InBev) signals to its competitors that if they lower prices, it will start a vicious retail war."
a. What does the article mean by a "retail war"?
b. Why would Anheuser-Busch threaten to start a retail war?