This chapter follows the globalization and radicalization of the policies on enemy aliens that occurred in the last two years of the war. In 1917, the conflict became truly global with the entrance of the Americas (the United States, Brazil and Cuba) and Asia (the independent states of China and Siam, and the Philippines as a US dependency). At the same time, Russia and Romania exited the conflict, signing disadvantageous peace agreements with Germany. All the states that joined the war in 1917 drew up policies against enemy aliens, notwithstanding the enormous differences in the numbers of such people within their territories. The chapter analyzes the policies against enemy aliens in the United States, in Brazil, in China and Siam, and compares them with the evolution of the war in Europe where radicalization transformed all foreigners into enemies and also affected neutral countries. The chapter concentrates in particular on a series of new developments that concerned property rights. On the eve of the end of the conflict, property rights were no longer safe in any of the belligerent countries and were actually in pieces in many places.