The post-war years of 1948 to 1955 ushered in the modern era of baseball cards. It was the result of what Dean Hanley describes in his new book, The Bubble Gum Card War, as "the perfect storm." With the end of World War II, rationing also came to end. Bubble gum manufacturing came back in full production. The key ingredients to make the sugary treat were, once again, readily available.