Answer:
Italy had the sharpest decline in immigration
Germany was the only county which increased from 1921 to 1929
Nixon needed China in negotiations with Vietnam.
-China is the most populated nation in world and wanted to have commercial relations
-Play USSR and China off one another
-Nixon would not be accused of being "soft on communism"
Answer:
Northern states favored tariffs because they helped strengthen their industrial-based economy.
B: The Federal Government needs to respond quickly.
Congress needs to go through a long and careful process to get things done, not to mention them needing to have the majority of congress agree.
The president/executive branch of the government is made up of much less people, as well as the president himself being commander and chief of the military.
Time is very important during a national emergency, and the president can get things done quickly.
Hope this helps.