We know lots of American Jews left Judaism in the pre-war years but is it right to blame this on America? I am not sure. First, the "dignified orthodox" lived in America, yet managed to stay orthodox over many generations, keeping their children and their grandchildren, and even their great-grandchildren in the fold. The group that left Judaism soon after arriving here were Eastern Europeans, but huge numbers of them dropped out while they were still in Europe where legions of EE Jews became communists, or socialists, or anarchists, or Zionists, etc.
This didn't happen in Germany. In Germany, Jews looked for ways to change Judaism, and they dropped observances (for both negative and positive reasons) but they (generally) didn't drop the religion (At first) (Abandonment of the religion was often the outcome of reform, but never the original intention).
Only in Eastern Europe (I think) did people drop out in huge numbers, a phenomenon that was replicated in America, but perhaps shouldn't be blamed on it.
In the 19th century German Jews attempted to reform Judaism, whereas Eastern European Jews dropped out. What accounts for the two difference responses?