Is globalization nothing new?

People have been sharing goods, services, and ideas for many years. It is much easier today, given the technology available to us. In Cohen and Kennedy's Global Sociology, they discuss major historic events and its relation to globalization. Since 1945, the United States has become the dominant power militarily and economically. My question is, if this idea of globalization is nothing new, why do a lot of people struggle with accepting it?