Answer:
Split US allegiance--During World War I, the US people were split on who to help and the same was true for Jefferson and Madison during the Napoleonic Wars between Britain and France.
Jefferson and Madison attempted to remain neutral in the conflict between Britain and France during the Napoleonic Wars because NE had a trade relationship with Britain but many believed the US owed an alliance to France after they helped during the Revolution.
Wilson faced a similar issue as immigration had created a diverse US population with support on both sides of World War I. Creating an alliance with either side could split the country and create problems within the US.
Answer:
Because they have done stuff like that in the past and they are very strict.
The nativists believed that long-ago immigrants from Western Europe could become real Americans. Nativists usually believe that some skills are set into the brain at birth, or "Native". They also thought that American views were connected to Protestant Christianity.