As immigrants arrived from many nations, why did it become necessary to restrict who and how many came to america?

well the lessons we can learn is how quickly our fragile freedoms can be overcome. mccarthy rose to power in 1950 of a tsunami of anti-communist hysteria, brandishing a lost of "known communists" in the state department, and held public trials to enhance his political clout. he had fallen from power but only when his attacks were against the u.s. army broadcast to millions of americans to their homes exposing his indecent persecution of the innocence of people. the senate censured him in december 1954 disgraced and discredited, he had died three years later at the age of 47..i hope my answer has you.. good day to you..

silk

indigo  

rice

all the other answers are wrong