In what way did the Aschluss present a challenge to the United States and its allies?

Anschluss was the name of the union of Austria and Germany in March 1938. It happened after the collapse of the Habsburg. After the annexation, the US criticized the chaos in Germany and formulated a foreign policy in order to respond to Hitler's aggressive foreign policy. This was a problem for the US and the allies because it showed that Hitler had no care for peace and got even more strongly with the annexation of Austria - it subsequently increased the size of Germany's military -.