After World War II, Australia believed that it must increase its population to avoid the threat of another invasion and launched an immigration program whose goal was to increase Australia's population with the slogan "populate or perish". Hundreds of thousands of displaced Europeans immigrated to Australia with more than three million people immigrating from Europe during the late 1940s until the 1960s. The Immigration Minister, Arthur Calwell, introduced the Assisted Passage Migration Scheme in 1945. The government was still trying to increase Australia's population, especially with people who have skills in the secondary industry sector. As the world was transforming into a more industrial and technological world, Australia needed to keep up.