What was "the New Imperialism"

As the book says imperialism is the domination by one country of the political, economic, or cultural life of another country or region. It is called the "new Imperialism" because by the 19Th and 20Th century Europe had strong centrally governed nation-states that had emerged, and from their new economic and military strength they were ready to embark on a path of aggressive expansion. The reason for expanding was basically because of the economy interests and the political and military interests.