|Spoiler Alert: This page contains spoilers. Read at your own risk.|
Australia (オーストラリア Ōsutoraria) is one of the countries in the Mahouka Koukou No Rettousei universe.
Australia took nominal measures in order to prevent terrorists from entering the country. The measures taken substantially stemmed immigration because of the strict policy of not letting people enter and leave the country with ease by closing international civilian airports. 
Australia chose de facto seclusion in order to avoid being caught up in World War III, and continues to be a neutral nation.  Even after having cut off foreign relations, Australia still maintains limited private trade with foreign countries. 
After World War III the British Commonwealth is said to have disappeared both in name and reality, however, a new British Commonwealth exists that conducts covert operations. 
Australia doesn't adhere completely to full neutrality. It's not uncommon for it to partner with an armed organization or join along with other countries in the illegal operations conducted in secret. 
"Darwin" Royal Australian Air Force Base 
Australia has an abundance of mineral resources and has managed to create self-sustaining agriculture, thus the country itself is self-sufficient.  Tying to historical reasons, Australia has minimal military technology and relies on the United Kingdom due to it being a technologically developed country like the USNA. 
There is a magician augmentation research manufacturing facility that's been protected by a deep air defense underground shelter. Since the postwar time, William McCloud has continued to guide the manufacturing of Australian Army magicians.